Question

递归算法 m和A和n个B，求有多少种排列

Answer 1

intf(intn){if(n==0||n==1)return1;elsereturnn*f(n-1);}voidmain(){intn,m;scanf("%d,%d",&n,&m);printf("n!/(m!*(n-m)!)=%f\n",(float)f(n)/(f(m)*f(n-m)));}