题解 | #牛牛的排列数#
牛牛的排列数
https://www.nowcoder.com/practice/9ca1c236cdbf46da9e08e1f510808625
#include <stdio.h> int order_A(int m,int n){ return m>1?order_A(m-1,n)*(n-m+1):n; } int main() { int m,n; scanf("%d %d",&n,&m); printf("%d",order_A(m,n)); return 0; }