include #include int jc(int m){if(m!=1) return m*jc(m-1);else return 1;} int c(int m,int n){if(m>=n) return jc(m)/(jc(n)*jc(m-n));} int main(void){int m,n;scanf("%d%d",&m,&n);printf("%d\n",c(m,n));return 0;}