题解 | #牛牛的排列数#
牛牛的排列数
https://www.nowcoder.com/practice/9ca1c236cdbf46da9e08e1f510808625
#include <stdio.h> int A(int n, int m) { if (n == m) { return 1; } return n * A(n-1,m); } int main() { int a, b; while (scanf("%d %d", &a, &b) != EOF) { int ret = A(a, b); printf("%d\n", ret); } return 0; }