19下列由C語言程式撰寫的函數sort實作了何種排序法？void sort (int a[], int l, int h) {if (l >= h) return;int j, i, key;i=l; j=h; key=a[i];while (i < j) {while (i < j&&a[j] > key) j--;if (i < j) a[i++] = a[j];while (i < j&&a[i]< key) i++;if (i < j) a[j--] = a[i];}a[i] = key;if (l < i-1)sort (a, l, i-1);if (i+1 < h)sort (a, i+1, h);}