quick sort algorithm

void quick_sort(int a[], int l, int r) { int i, m; if(l >= r) return; for(m = l, i = l+1; i <= r; i++) if(a[i] < a[l]) swap(a, i, ++m); swap(a, l, m); quick_sort(a, l, m); quick_sort(a, m+1, r); }