Java-Sort-Algorithms/QuickSort.java at master · mattryanmtl/Java-Sort-Algorithms · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
importjava.io.BufferedReader;

importjava.io.InputStreamReader;

importjava.util.Arrays;

importjava.util.Random;


publicclassQuickSort {

// Function to partion the array on the basis of the pivot value;

staticintpartition(int[] array, intlow, inthigh) {

intj, temp, i = low + 1;

Randomrandom = newRandom();

intx = random.nextInt(high - low) + low;

temp = array[low];

array[low] = array[x];

array[x] = temp;

for (j = low + 1; j <= high; j++) {

if (array[j] <= array[low] && j != i) {

temp = array[j];

array[j] = array[i];

array[i++] = temp;

 } elseif (array[j] <= array[low]) {

i++;

 }

 }

temp = array[i - 1];

array[i - 1] = array[low];

array[low] = temp;

returni - 1;

 }

// Function to implement quick sort

staticvoidquickSort(int[] array,intlow,inthigh){

if(low<high){

intmid = partition(array,low,high);

quickSort(array,low,mid-1);

quickSort(array,mid+1,high);

 }

 }

// Function to read user input

publicstaticvoidmain(String[] args) {

BufferedReaderbr = newBufferedReader(newInputStreamReader(System.in));

intsize;

System.out.println("Enter the size of the array");

try {

size = Integer.parseInt(br.readLine());

 } catch (Exceptione) {

System.out.println("Invalid Input");

return;

 }

int[] array = newint[size];

System.out.println("Enter array elements");

inti;

for (i = 0; i < array.length; i++) {

try {

array[i] = Integer.parseInt(br.readLine());

 } catch (Exceptione) {

System.out.println("An error Occurred");

 }

 }

System.out.println("The initial array is");

System.out.println(Arrays.toString(array));

quickSort(array,0,array.length-1);

System.out.println("The sorted array is");

System.out.println(Arrays.toString(array));

 }

}