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reverse linked list in groups of given size #9326

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reverse linked list of groups of given size
pa-kh039 Oct 1, 2023
4c0207e
minor changes as suggested
pa-kh039 Oct 1, 2023
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125 changes: 125 additions & 0 deletions data_structures/linked_list/reverse_in_group_of_given_size.py
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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
data: int
nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
"""
Insert a new node at the end of a linked list and return the new head.
>>> head = insert_node(None, 1)
>>> head = insert_node(head, 2)
>>> head = insert_node(head, 3)
>>> print_linked_list(head)
1->2->3
"""
new_node = Node(data)
# If the linked list is empty, the new_node becomes the head
if head is None:
return new_node

temp_node = head
while temp_node.nextt is not None:
temp_node = temp_node.nextt

temp_node.nextt = new_node # type: ignore
return head


def length_of_linked_list(head: Node | None) -> int:
"""
find length of linked list
>>> head = insert_node(None, 10)
>>> head = insert_node(head, 9)
>>> head = insert_node(head, 8)
>>> length_of_linked_list(head)
3
"""
length = 0
while head is not None:
length += 1
head = head.nextt
return length


def print_linked_list(head: Node | None) -> None:
"""
print the entire linked list
>>> head = insert_node(None, 1)
>>> head = insert_node(head, 2)
>>> head = insert_node(head, 3)
>>> print_linked_list(head)
1->2->3
"""
if head is not None:
while head.nextt is not None:
print(head.data, end="->")
head = head.nextt
print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
"""
reverse nodes within groups of size k
>>> head = insert_node(None, 1)
>>> head = insert_node(head, 2)
>>> head = insert_node(head, 3)
>>> head = insert_node(head, 4)
>>> head = insert_node(head, 5)
>>> new_head = reverse_k_nodes(head, 2)
>>> print_linked_list(new_head)
2->1->4->3->5
"""
if head is None or head.nextt is None:
return head

length = length_of_linked_list(head)

dummy_head = Node(0)
dummy_head.nextt = head

previous_node = dummy_head

while length >= group_size:
assert previous_node
current_node = previous_node.nextt
assert current_node
next_node = current_node.nextt
for _ in range(1, group_size):
assert next_node, current_node
current_node.nextt = next_node.nextt
assert previous_node
next_node.nextt = previous_node.nextt
assert previous_node
previous_node.nextt = next_node
assert current_node
next_node = current_node.nextt
previous_node = current_node
length -= group_size
assert dummy_head
return dummy_head.nextt


if __name__ == "__main__":
from doctest import testmod

testmod()

k = 2
head = insert_node(None, 1)
head = insert_node(head, 2)
head = insert_node(head, 3)
head = insert_node(head, 4)
head = insert_node(head, 5)

print("Original Linked List: ", end="")
print_linked_list(head)
print("After Reversal of k nodes: ", end="")
new_head = reverse_k_nodes(head, k)
print_linked_list(new_head)
print()
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document.querySelectorAll('pre code').forEach(function(codeBlock) {
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})();
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try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
reverse linked list in groups of given size by pa-kh039 · Pull Request #9326 · TheAlgorithms/Python · GitHub
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reverse linked list in groups of given size#9326

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reverse linked list in groups of given size
#9326
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714d6aa

reverse linked list of groups of given size


pa-kh039 Oct 1, 2023
4c0207e

minor changes as suggested


pa-kh039 Oct 1, 2023

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125 changes: 125 additions & 0 deletions
data_structures/linked_list/reverse_in_group_of_given_size.py

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
 data: int
 nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
 """
 Insert a new node at the end of a linked list and return the new head.
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 new_node = Node(data)
 # If the linked list is empty, the new_node becomes the head
 if head is None:
 return new_node

 temp_node = head
 while temp_node.nextt is not None:
 temp_node = temp_node.nextt

 temp_node.nextt = new_node # type: ignore
 return head


def length_of_linked_list(head: Node | None) -> int:
 """
 find length of linked list
 >>> head = insert_node(None, 10)
 >>> head = insert_node(head, 9)
 >>> head = insert_node(head, 8)
 >>> length_of_linked_list(head)
 3
 """
 length = 0
 while head is not None:
 length += 1
 head = head.nextt
 return length


def print_linked_list(head: Node | None) -> None:
 """
 print the entire linked list
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 if head is not None:
 while head.nextt is not None:
 print(head.data, end="->")
 head = head.nextt
 print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
 """
 reverse nodes within groups of size k
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> head = insert_node(head, 4)
 >>> head = insert_node(head, 5)
 >>> new_head = reverse_k_nodes(head, 2)
 >>> print_linked_list(new_head)
 2->1->4->3->5
 """
 if head is None or head.nextt is None:
 return head

 length = length_of_linked_list(head)

 dummy_head = Node(0)
 dummy_head.nextt = head

 previous_node = dummy_head

 while length >= group_size:
 assert previous_node
 current_node = previous_node.nextt
 assert current_node
 next_node = current_node.nextt
 for _ in range(1, group_size):
 assert next_node, current_node
 current_node.nextt = next_node.nextt
 assert previous_node
 next_node.nextt = previous_node.nextt
 assert previous_node
 previous_node.nextt = next_node
 assert current_node
 next_node = current_node.nextt
 previous_node = current_node
 length -= group_size
 assert dummy_head
 return dummy_head.nextt


if __name__ == "__main__":
 from doctest import testmod

 testmod()

 k = 2
 head = insert_node(None, 1)
 head = insert_node(head, 2)
 head = insert_node(head, 3)
 head = insert_node(head, 4)
 head = insert_node(head, 5)

 print("Original Linked List: ", end="")
 print_linked_list(head)
 print("After Reversal of k nodes: ", end="")
 new_head = reverse_k_nodes(head, k)
 print_linked_list(new_head)
 print()

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Force GitHub README to respect dark mode
(function() {
var style = document.createElement('style');
style.textContent = '
.markdown-body {
color-scheme: dark light;
}
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';
document.head.appendChild(style);
})();
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
reverse linked list in groups of given size by pa-kh039 · Pull Request #9326 · TheAlgorithms/Python · GitHub
Skip to content
reverse linked list in groups of given size#9326

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reverse linked list in groups of given size
#9326
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714d6aa

reverse linked list of groups of given size


pa-kh039 Oct 1, 2023
4c0207e

minor changes as suggested


pa-kh039 Oct 1, 2023

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125 changes: 125 additions & 0 deletions
data_structures/linked_list/reverse_in_group_of_given_size.py

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
 data: int
 nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
 """
 Insert a new node at the end of a linked list and return the new head.
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 new_node = Node(data)
 # If the linked list is empty, the new_node becomes the head
 if head is None:
 return new_node

 temp_node = head
 while temp_node.nextt is not None:
 temp_node = temp_node.nextt

 temp_node.nextt = new_node # type: ignore
 return head


def length_of_linked_list(head: Node | None) -> int:
 """
 find length of linked list
 >>> head = insert_node(None, 10)
 >>> head = insert_node(head, 9)
 >>> head = insert_node(head, 8)
 >>> length_of_linked_list(head)
 3
 """
 length = 0
 while head is not None:
 length += 1
 head = head.nextt
 return length


def print_linked_list(head: Node | None) -> None:
 """
 print the entire linked list
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 if head is not None:
 while head.nextt is not None:
 print(head.data, end="->")
 head = head.nextt
 print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
 """
 reverse nodes within groups of size k
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> head = insert_node(head, 4)
 >>> head = insert_node(head, 5)
 >>> new_head = reverse_k_nodes(head, 2)
 >>> print_linked_list(new_head)
 2->1->4->3->5
 """
 if head is None or head.nextt is None:
 return head

 length = length_of_linked_list(head)

 dummy_head = Node(0)
 dummy_head.nextt = head

 previous_node = dummy_head

 while length >= group_size:
 assert previous_node
 current_node = previous_node.nextt
 assert current_node
 next_node = current_node.nextt
 for _ in range(1, group_size):
 assert next_node, current_node
 current_node.nextt = next_node.nextt
 assert previous_node
 next_node.nextt = previous_node.nextt
 assert previous_node
 previous_node.nextt = next_node
 assert current_node
 next_node = current_node.nextt
 previous_node = current_node
 length -= group_size
 assert dummy_head
 return dummy_head.nextt


if __name__ == "__main__":
 from doctest import testmod

 testmod()

 k = 2
 head = insert_node(None, 1)
 head = insert_node(head, 2)
 head = insert_node(head, 3)
 head = insert_node(head, 4)
 head = insert_node(head, 5)

 print("Original Linked List: ", end="")
 print_linked_list(head)
 print("After Reversal of k nodes: ", end="")
 new_head = reverse_k_nodes(head, k)
 print_linked_list(new_head)
 print()

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Highlight search terms from Google/DuckDuckGo/Bing referrer
(function() {
var ref = document.referrer;
var terms = [];
if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {
var url = new URL(ref);
var q = url.searchParams.get('q') || url.searchParams.get('p');
if (q) {
terms = q.split(/\s+/).filter(function(t) { return t.length > 2; });
}
}
if (terms.length === 0) return;
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style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';
document.head.appendChild(style);
function highlight(node) {
if (node.nodeType === 3) { // text node
var text = node.textContent;
var found = false;
terms.forEach(function(term) {
var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\]\\]/g, '\\') + ')', 'gi');
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frag.appendChild(span);
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(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
reverse linked list in groups of given size by pa-kh039 · Pull Request #9326 · TheAlgorithms/Python · GitHub
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reverse linked list in groups of given size#9326

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reverse linked list in groups of given size
#9326
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714d6aa

reverse linked list of groups of given size


pa-kh039 Oct 1, 2023
4c0207e

minor changes as suggested


pa-kh039 Oct 1, 2023

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125 changes: 125 additions & 0 deletions
data_structures/linked_list/reverse_in_group_of_given_size.py

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
 data: int
 nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
 """
 Insert a new node at the end of a linked list and return the new head.
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 new_node = Node(data)
 # If the linked list is empty, the new_node becomes the head
 if head is None:
 return new_node

 temp_node = head
 while temp_node.nextt is not None:
 temp_node = temp_node.nextt

 temp_node.nextt = new_node # type: ignore
 return head


def length_of_linked_list(head: Node | None) -> int:
 """
 find length of linked list
 >>> head = insert_node(None, 10)
 >>> head = insert_node(head, 9)
 >>> head = insert_node(head, 8)
 >>> length_of_linked_list(head)
 3
 """
 length = 0
 while head is not None:
 length += 1
 head = head.nextt
 return length


def print_linked_list(head: Node | None) -> None:
 """
 print the entire linked list
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 if head is not None:
 while head.nextt is not None:
 print(head.data, end="->")
 head = head.nextt
 print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
 """
 reverse nodes within groups of size k
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> head = insert_node(head, 4)
 >>> head = insert_node(head, 5)
 >>> new_head = reverse_k_nodes(head, 2)
 >>> print_linked_list(new_head)
 2->1->4->3->5
 """
 if head is None or head.nextt is None:
 return head

 length = length_of_linked_list(head)

 dummy_head = Node(0)
 dummy_head.nextt = head

 previous_node = dummy_head

 while length >= group_size:
 assert previous_node
 current_node = previous_node.nextt
 assert current_node
 next_node = current_node.nextt
 for _ in range(1, group_size):
 assert next_node, current_node
 current_node.nextt = next_node.nextt
 assert previous_node
 next_node.nextt = previous_node.nextt
 assert previous_node
 previous_node.nextt = next_node
 assert current_node
 next_node = current_node.nextt
 previous_node = current_node
 length -= group_size
 assert dummy_head
 return dummy_head.nextt


if __name__ == "__main__":
 from doctest import testmod

 testmod()

 k = 2
 head = insert_node(None, 1)
 head = insert_node(head, 2)
 head = insert_node(head, 3)
 head = insert_node(head, 4)
 head = insert_node(head, 5)

 print("Original Linked List: ", end="")
 print_linked_list(head)
 print("After Reversal of k nodes: ", end="")
 new_head = reverse_k_nodes(head, k)
 print_linked_list(new_head)
 print()

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Strip utm_, fbclid, gclid, etc. from all links on page
(function() {
var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',
'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
'ref', 'ref_src', 'source', 'medium', 'campaign'];
function cleanUrl(url) {
try {
var u = new URL(url, window.location.origin);
var changed = false;
trackingParams.forEach(function(p) {
if (u.searchParams.has(p)) {
u.searchParams.delete(p);
changed = true;
}
});
return changed ? u.toString() : url;
} catch (e) {
return url;
}
}
function cleanLinks() {
document.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
cleanLinks();
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mutations.forEach(function(m) {
m.addedNodes.forEach(function(node) {
if (node.nodeType === 1) {
if (node.tagName === 'A') cleanLinks();
node.querySelectorAll('a[href]').forEach(function(a) {
var clean = cleanUrl(a.href);
if (clean !== a.href) a.href = clean;
});
}
});
});
});
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
reverse linked list in groups of given size by pa-kh039 · Pull Request #9326 · TheAlgorithms/Python · GitHub
Skip to content
reverse linked list in groups of given size#9326

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pa-kh039
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reverse linked list in groups of given size
#9326
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714d6aa

reverse linked list of groups of given size


pa-kh039 Oct 1, 2023
4c0207e

minor changes as suggested


pa-kh039 Oct 1, 2023

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125 changes: 125 additions & 0 deletions
data_structures/linked_list/reverse_in_group_of_given_size.py

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
 data: int
 nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
 """
 Insert a new node at the end of a linked list and return the new head.
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 new_node = Node(data)
 # If the linked list is empty, the new_node becomes the head
 if head is None:
 return new_node

 temp_node = head
 while temp_node.nextt is not None:
 temp_node = temp_node.nextt

 temp_node.nextt = new_node # type: ignore
 return head


def length_of_linked_list(head: Node | None) -> int:
 """
 find length of linked list
 >>> head = insert_node(None, 10)
 >>> head = insert_node(head, 9)
 >>> head = insert_node(head, 8)
 >>> length_of_linked_list(head)
 3
 """
 length = 0
 while head is not None:
 length += 1
 head = head.nextt
 return length


def print_linked_list(head: Node | None) -> None:
 """
 print the entire linked list
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 if head is not None:
 while head.nextt is not None:
 print(head.data, end="->")
 head = head.nextt
 print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
 """
 reverse nodes within groups of size k
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> head = insert_node(head, 4)
 >>> head = insert_node(head, 5)
 >>> new_head = reverse_k_nodes(head, 2)
 >>> print_linked_list(new_head)
 2->1->4->3->5
 """
 if head is None or head.nextt is None:
 return head

 length = length_of_linked_list(head)

 dummy_head = Node(0)
 dummy_head.nextt = head

 previous_node = dummy_head

 while length >= group_size:
 assert previous_node
 current_node = previous_node.nextt
 assert current_node
 next_node = current_node.nextt
 for _ in range(1, group_size):
 assert next_node, current_node
 current_node.nextt = next_node.nextt
 assert previous_node
 next_node.nextt = previous_node.nextt
 assert previous_node
 previous_node.nextt = next_node
 assert current_node
 next_node = current_node.nextt
 previous_node = current_node
 length -= group_size
 assert dummy_head
 return dummy_head.nextt


if __name__ == "__main__":
 from doctest import testmod

 testmod()

 k = 2
 head = insert_node(None, 1)
 head = insert_node(head, 2)
 head = insert_node(head, 3)
 head = insert_node(head, 4)
 head = insert_node(head, 5)

 print("Original Linked List: ", end="")
 print_linked_list(head)
 print("After Reversal of k nodes: ", end="")
 new_head = reverse_k_nodes(head, k)
 print_linked_list(new_head)
 print()

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
(function() {
function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
if (btn && !btn.classList.contains('activated')) {
btn.click();
}
}
// Try immediately
tryTheater();
// Try after navigation (SPA)
var lastUrl = location.href;
setInterval(function() {
if (location.href !== lastUrl) {
lastUrl = location.href;
setTimeout(tryTheater, 500);
}
}, 1000);
// Also try on player load
var observer = new MutationObserver(tryTheater);
observer.observe(document.body, { childList: true, subtree: true });
})();
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
reverse linked list in groups of given size by pa-kh039 · Pull Request #9326 · TheAlgorithms/Python · GitHub
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reverse linked list in groups of given size
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reverse linked list of groups of given size


pa-kh039 Oct 1, 2023
4c0207e

minor changes as suggested


pa-kh039 Oct 1, 2023

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data_structures/linked_list/reverse_in_group_of_given_size.py

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
 data: int
 nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
 """
 Insert a new node at the end of a linked list and return the new head.
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 new_node = Node(data)
 # If the linked list is empty, the new_node becomes the head
 if head is None:
 return new_node

 temp_node = head
 while temp_node.nextt is not None:
 temp_node = temp_node.nextt

 temp_node.nextt = new_node # type: ignore
 return head


def length_of_linked_list(head: Node | None) -> int:
 """
 find length of linked list
 >>> head = insert_node(None, 10)
 >>> head = insert_node(head, 9)
 >>> head = insert_node(head, 8)
 >>> length_of_linked_list(head)
 3
 """
 length = 0
 while head is not None:
 length += 1
 head = head.nextt
 return length


def print_linked_list(head: Node | None) -> None:
 """
 print the entire linked list
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 if head is not None:
 while head.nextt is not None:
 print(head.data, end="->")
 head = head.nextt
 print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
 """
 reverse nodes within groups of size k
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> head = insert_node(head, 4)
 >>> head = insert_node(head, 5)
 >>> new_head = reverse_k_nodes(head, 2)
 >>> print_linked_list(new_head)
 2->1->4->3->5
 """
 if head is None or head.nextt is None:
 return head

 length = length_of_linked_list(head)

 dummy_head = Node(0)
 dummy_head.nextt = head

 previous_node = dummy_head

 while length >= group_size:
 assert previous_node
 current_node = previous_node.nextt
 assert current_node
 next_node = current_node.nextt
 for _ in range(1, group_size):
 assert next_node, current_node
 current_node.nextt = next_node.nextt
 assert previous_node
 next_node.nextt = previous_node.nextt
 assert previous_node
 previous_node.nextt = next_node
 assert current_node
 next_node = current_node.nextt
 previous_node = current_node
 length -= group_size
 assert dummy_head
 return dummy_head.nextt


if __name__ == "__main__":
 from doctest import testmod

 testmod()

 k = 2
 head = insert_node(None, 1)
 head = insert_node(head, 2)
 head = insert_node(head, 3)
 head = insert_node(head, 4)
 head = insert_node(head, 5)

 print("Original Linked List: ", end="")
 print_linked_list(head)
 print("After Reversal of k nodes: ", end="")
 new_head = reverse_k_nodes(head, k)
 print_linked_list(new_head)
 print()

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Remove or un-stick sticky/fixed headers that block content
(function() {
function unstick() {
document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) {
if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {
el.style.position = 'static';
el.style.top = 'auto';
el.style.zIndex = 'auto';
}
});
}
unstick();
var observer = new MutationObserver(unstick);
observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });
})();
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
reverse linked list in groups of given size by pa-kh039 · Pull Request #9326 · TheAlgorithms/Python · GitHub
Skip to content
reverse linked list in groups of given size#9326

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 Closed

pa-kh039
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from

 Closed


reverse linked list in groups of given size
#9326
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714d6aa

reverse linked list of groups of given size


pa-kh039 Oct 1, 2023
4c0207e

minor changes as suggested


pa-kh039 Oct 1, 2023

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125 changes: 125 additions & 0 deletions
data_structures/linked_list/reverse_in_group_of_given_size.py

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
 data: int
 nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
 """
 Insert a new node at the end of a linked list and return the new head.
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 new_node = Node(data)
 # If the linked list is empty, the new_node becomes the head
 if head is None:
 return new_node

 temp_node = head
 while temp_node.nextt is not None:
 temp_node = temp_node.nextt

 temp_node.nextt = new_node # type: ignore
 return head


def length_of_linked_list(head: Node | None) -> int:
 """
 find length of linked list
 >>> head = insert_node(None, 10)
 >>> head = insert_node(head, 9)
 >>> head = insert_node(head, 8)
 >>> length_of_linked_list(head)
 3
 """
 length = 0
 while head is not None:
 length += 1
 head = head.nextt
 return length


def print_linked_list(head: Node | None) -> None:
 """
 print the entire linked list
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 if head is not None:
 while head.nextt is not None:
 print(head.data, end="->")
 head = head.nextt
 print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
 """
 reverse nodes within groups of size k
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> head = insert_node(head, 4)
 >>> head = insert_node(head, 5)
 >>> new_head = reverse_k_nodes(head, 2)
 >>> print_linked_list(new_head)
 2->1->4->3->5
 """
 if head is None or head.nextt is None:
 return head

 length = length_of_linked_list(head)

 dummy_head = Node(0)
 dummy_head.nextt = head

 previous_node = dummy_head

 while length >= group_size:
 assert previous_node
 current_node = previous_node.nextt
 assert current_node
 next_node = current_node.nextt
 for _ in range(1, group_size):
 assert next_node, current_node
 current_node.nextt = next_node.nextt
 assert previous_node
 next_node.nextt = previous_node.nextt
 assert previous_node
 previous_node.nextt = next_node
 assert current_node
 next_node = current_node.nextt
 previous_node = current_node
 length -= group_size
 assert dummy_head
 return dummy_head.nextt


if __name__ == "__main__":
 from doctest import testmod

 testmod()

 k = 2
 head = insert_node(None, 1)
 head = insert_node(head, 2)
 head = insert_node(head, 3)
 head = insert_node(head, 4)
 head = insert_node(head, 5)

 print("Original Linked List: ", end="")
 print_linked_list(head)
 print("After Reversal of k nodes: ", end="")
 new_head = reverse_k_nodes(head, k)
 print_linked_list(new_head)
 print()

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Universal Dark Mode - works on any site
(function() {
var enabled = true;
function applyDarkMode() {
if (!enabled) return;
// Create style element if it doesn't exist
var style = document.getElementById('universal-dark-mode-style');
if (!style) {
style = document.createElement('style');
style.id = 'universal-dark-mode-style';
document.head.appendChild(style);
}
// Dark mode CSS - inverts colors but preserves images/video
style.textContent = '
/* Invert everything except media */
html {
filter: invert(1) hue-rotate(180deg) !important;
background: #1a1a2e !important;
}
/* Restore images, videos, iframes, canvas */
img, video, iframe, canvas, svg, picture, [style*="background-image"] {
filter: invert(1) hue-rotate(180deg) !important;
}
/* Preserve specific elements that should not be inverted */
.no-dark-mode, .no-dark-mode *,
[data-theme="light"], [data-theme="light"],
.ace_editor, .ace_editor *,
.CodeMirror, .CodeMirror *,
.monaco-editor, .monaco-editor *,
.markdown-body pre, .markdown-body pre *,
.highlight, .highlight *,
pre code, pre code * {
filter: none !important;
}
/* Fix common UI elements */
.modal, .popup, .dropdown-menu, .tooltip, .popover {
filter: invert(1) hue-rotate(180deg) !important;
background: #2d2d44 !important;
border-color: #444 !important;
}
/* Scrollbars */
::-webkit-scrollbar { background: #1a1a2e !important; }
::-webkit-scrollbar-thumb { background: #444 !important; }
::-webkit-scrollbar-thumb:hover { background: #555 !important; }
/* Selection */
::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }
';
}
function removeDarkMode() {
var style = document.getElementById('universal-dark-mode-style');
if (style) style.remove();
}
// Toggle with Alt+Shift+D
document.addEventListener('keydown', function(e) {
if (e.altKey && e.shiftKey && e.key === 'D') {
e.preventDefault();
enabled = !enabled;
if (enabled) {
applyDarkMode();
console.log('[Universal Dark Mode] Enabled');
} else {
removeDarkMode();
console.log('[Universal Dark Mode] Disabled');
}
}
});
// Apply on load
applyDarkMode();
// Re-apply on dynamic content
var observer = new MutationObserver(function(mutations) {
if (enabled && !document.getElementById('universal-dark-mode-style')) {
applyDarkMode();
}
});
observer.observe(document.head, { childList: true });
console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');
})();
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();
reverse linked list in groups of given size by pa-kh039 · Pull Request #9326 · TheAlgorithms/Python · GitHub
Skip to content
reverse linked list in groups of given size#9326

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 Closed

pa-kh039
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2
commits into

from

 Closed


reverse linked list in groups of given size
#9326
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714d6aa

reverse linked list of groups of given size


pa-kh039 Oct 1, 2023
4c0207e

minor changes as suggested


pa-kh039 Oct 1, 2023

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125 changes: 125 additions & 0 deletions
data_structures/linked_list/reverse_in_group_of_given_size.py

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Open in desktop

Original file line numberDiff line numberDiff line change
@@ -0,0 +1,125 @@
from __future__ import annotations

from dataclasses import dataclass


@dataclass
class Node:
 data: int
 nextt: Node | None = None


def insert_node(head: Node | None, data: int) -> Node:
 """
 Insert a new node at the end of a linked list and return the new head.
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 new_node = Node(data)
 # If the linked list is empty, the new_node becomes the head
 if head is None:
 return new_node

 temp_node = head
 while temp_node.nextt is not None:
 temp_node = temp_node.nextt

 temp_node.nextt = new_node # type: ignore
 return head


def length_of_linked_list(head: Node | None) -> int:
 """
 find length of linked list
 >>> head = insert_node(None, 10)
 >>> head = insert_node(head, 9)
 >>> head = insert_node(head, 8)
 >>> length_of_linked_list(head)
 3
 """
 length = 0
 while head is not None:
 length += 1
 head = head.nextt
 return length


def print_linked_list(head: Node | None) -> None:
 """
 print the entire linked list
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> print_linked_list(head)
 1->2->3
 """
 if head is not None:
 while head.nextt is not None:
 print(head.data, end="->")
 head = head.nextt
 print(head.data)


def reverse_k_nodes(head: Node | None, group_size: int) -> Node | None:
 """
 reverse nodes within groups of size k
 >>> head = insert_node(None, 1)
 >>> head = insert_node(head, 2)
 >>> head = insert_node(head, 3)
 >>> head = insert_node(head, 4)
 >>> head = insert_node(head, 5)
 >>> new_head = reverse_k_nodes(head, 2)
 >>> print_linked_list(new_head)
 2->1->4->3->5
 """
 if head is None or head.nextt is None:
 return head

 length = length_of_linked_list(head)

 dummy_head = Node(0)
 dummy_head.nextt = head

 previous_node = dummy_head

 while length >= group_size:
 assert previous_node
 current_node = previous_node.nextt
 assert current_node
 next_node = current_node.nextt
 for _ in range(1, group_size):
 assert next_node, current_node
 current_node.nextt = next_node.nextt
 assert previous_node
 next_node.nextt = previous_node.nextt
 assert previous_node
 previous_node.nextt = next_node
 assert current_node
 next_node = current_node.nextt
 previous_node = current_node
 length -= group_size
 assert dummy_head
 return dummy_head.nextt


if __name__ == "__main__":
 from doctest import testmod

 testmod()

 k = 2
 head = insert_node(None, 1)
 head = insert_node(head, 2)
 head = insert_node(head, 3)
 head = insert_node(head, 4)
 head = insert_node(head, 5)

 print("Original Linked List: ", end="")
 print_linked_list(head)
 print("After Reversal of k nodes: ", end="")
 new_head = reverse_k_nodes(head, k)
 print_linked_list(new_head)
 print()