Algorithm/etc
recursion memoization
DingCoDing
2022. 1. 18. 13:24
반응형
#include <stdio.h>
#include <iostream>
#include <algorithm>
#include <stack>
#include <vector>
#include <math.h>
#include <queue>
using namespace std;
// 5C3 = 4C2 + 4C3
int dy[21][21];
int DFS(int n, int r){
if(dy[n][r]>0) return dy[n][r];
if(r==0 || n==r) return 1;
else{
return dy[n][r] = DFS(n-1, r-1) + DFS(n-1, r);
}
}
int main() {
//freopen("input.txt.txt","rt",stdin);
int n, r;
scanf("%d %d", &n, &r);
printf("%d", DFS(n,r));
return 0;
}
반응형