DataStructures-Algorithms-Prep/3sum.py at main · Extomvi/DataStructures-Algorithms-Prep · GitHub

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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))
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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))
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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))
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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))
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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))
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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))
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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))
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"""
3 sum of a number
"""
# Leetcode: https://leetcode.com/problems/3sum/

#brute force
defthree_sum(nums):
n=len(nums)
foriinrange(n-2):
forjinrange(i+1, n-1):
forkinrange(j+1, n):
ifnums[i] +nums[j] +nums[k] ==0:
return [nums[i], nums[j], nums[k]]
return-1

#Using 2 pointers
defthreeSum(nums):
ifnotnumsandlen(nums) <3:
return []
result= []
nums.sort()
foriinrange(len(nums)):
ifi>0andnums[i] ==nums[i-1]:
continue
twoSum(nums, i, result)
print(result)

deftwoSum(nums, i, result):
left=i+1
right=len(nums) -1
whileleft<right:
total=nums[i] +nums[left] +nums[right]
iftotal==0:
result.append([nums[i], nums[left], nums[right]])
left+=1
right-=1

whileleft<rightandnums[left] ==nums[left-1]:
left+=1
whileleft<rightandnums[right] ==nums[right+1]:
right-=1
eliftotal<0:
left+=1
else:
right-=1

print(threeSum([2,3,-1,4,1,-3]))