61 lines
1.2 KiB
C
61 lines
1.2 KiB
C
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// Quick Sort Algorithm in C
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#include <stdio.h>
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// Function to swap two elements
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void swap(int *a, int *b)
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{
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int temp = *a;
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*a = *b;
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*b = temp;
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}
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/* This function takes first element as pivot, places the pivot element at its correct position in sorted array,
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and places all smaller (smaller than pivot) to left of pivot and all greater elements to right of pivot.*/
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int Partition(int a[], int low, int high)
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{
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int pivot = a[low];
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int start = low;
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int end = high;
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while (start < end)
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{
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while (a[start] <= pivot)
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start++;
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while (a[end] > pivot)
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end--;
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if (start < end)
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{
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swap(&a[start], &a[end]);
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}
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}
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swap(&a[low], &a[end]);
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return end;
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}
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// Recursive function to sort an array using quick sort
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void Quicksort(int a[], int low, int high)
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{
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if (low < high)
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{
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int pivot = Partition(a, low, high);
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Quicksort(a, low, pivot - 1);
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Quicksort(a, pivot + 1, high);
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}
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}
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int main()
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{
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int a[] = {5, 2, 4, 6, 1, 3};
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int n = sizeof(a) / sizeof(a[0]);
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Quicksort(a, 0, n - 1);
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for (int i = 0; i < n; i++){
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printf("%d ", a[i]);
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}
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return 0;
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}
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/*
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Output:
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1 2 3 4 5 6
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*/
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