백준 2293번 C++ 풀이

#include <iostream>
#include <algorithm>
#include <numeric>
using namespace std;
long long buffer[10001][3];
int coin[101];

int main() {

    ios::sync_with_stdio(false);
    cin.tie(NULL);
    int n,k;
    cin >> n >> k;
    for (int i=1; i<=n; i++){
        cin >>  coin[i];
    }
    for (int i =1; i<=k; i++){
        buffer[i][1] = (i%coin[1] == 0)? 1 : 0;
    }

    if (n > 1) {
        for (int j = 2; j <= n; j++) {
            for (int i = 1; i <= k; i++) {

                if (i - coin[j] == 0)  buffer[i][j % 2] = buffer[i][(j-1)%2] + 1;
                else if (i - coin[j] > 0) buffer[i][j %2] = buffer[i][(j - 1)%2] + buffer[i - coin[j]][j%2];
                else buffer[i][j%2] =  buffer[i][(j - 1)%2];
            }
        }
    }
//    for (int i = 1; i<=k ; i++){
//        for (int j = 1; j <= n; j++){
//            cout << i << ' ' << j<<' '<<buffer[i][j] << ' ';
//        }
//        cout << '\n';
//    }
    cout << buffer[k][n%2];
    return 0;
}