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#include <stdio.h> |
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|
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#define ARR_LEN 7 |
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|
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void qsort(int v[], int left, int right); |
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void printArr(int v[], int len); |
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|
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int main() |
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{ |
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int i; |
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int v[ARR_LEN] = { 4, 3, 1, 7, 9, 6, 2 }; |
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printArr(v, ARR_LEN); |
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qsort(v, 0, ARR_LEN-1); |
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printArr(v, ARR_LEN); |
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return 0; |
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} |
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|
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void qsort(int v[], int left, int right) |
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{ |
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int i, last; |
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void swap(int v[], int i, int j); |
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|
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if (left >= right) |
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return; |
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swap(v, left, (left + right) / 2); |
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last = left; |
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for (i = left+1; i <= right; i++) |
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if (v[i] < v[left]) |
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swap(v, ++last, i); |
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swap(v, left, last); |
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qsort(v, left, last-1); |
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qsort(v, last+1, right); |
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} |
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|
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void swap(int v[], int i, int j) |
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{ |
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int temp; |
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|
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temp = v[i]; |
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v[i] = v[j]; |
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v[j] = temp; |
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} |
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|
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void printArr(int v[], int len) |
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{ |
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int i; |
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for (i = 0; i < len; i++) |
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printf("%d ", v[i]); |
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printf("\n"); |
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} |
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|
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// From https://github.com/Heatwave/The-C-Programming-Language-2nd-Edition/blob/master/chapter-4-functions-and-program-structure/8.qsort.c |