binomial-memozation.cpp

#include <iostream>
#include <memory.h>
using namespace std;
#define MAXN 1500
int cashe[MAXN][MAXN];
int binomial(int n, int k, int p){
    if(cashe[n][k] != -1 ) return cashe[n][k];
    if(k ==0 || k == n)
        return cashe[n][k] = 1;
    return cashe[n][k] = (binomial(n-1, k-1, p)+binomial(n-1, k, p))%p;
}
int main(){
    memset(cashe, -1, sizeof(cashe));
    int N, K;
    cin >> N >> K;
    cout << binomial(N, K, 7) << endl;
    return 0;
}