常用算法的简洁代码实现之快速排序归并排序

Posted 2021-07-27 不染尘埃

快速排序模板

题目链接：https://www.acwing.com/problem/content/787/

void quick_sort(int q[], int l, int r){    if (l >= r) return;     int i = l - 1, j = r + 1, x = q[l + r >> 1]; while (i < j) { do i ++ ; while (q[i] < x); do j -- ; while (q[j] > x); if (i < j) swap(q[i], q[j]); } quick_sort(q, l, j), quick_sort(q, j + 1, r);}

归并排序模板

题目链接：https://www.acwing.com/problem/content/789/

void merge_sort(int q[], int l, int r){ if (l >= r) return; int mid = l + r >> 1; merge_sort(q, l, mid); merge_sort(q, mid + 1, r);
 int k = 0, i = l, j = mid + 1; while (i <= mid && j <= r) if (q[i] <= q[j]) tmp[k ++ ] = q[i ++ ];        else tmp[k ++ ] = q[j ++ ];         while (i <= mid) tmp[k ++ ] = q[i ++ ];    while (j <= r) tmp[k ++ ] = q[j ++ ]; for (i = l, j = 0; i <= r; i ++, j ++ ) q[i] = tmp[j];}