Submission

Score: 100

User: tHeNyXs

Problemset: กองไฟ

Language: cpp

Time: 0.005 second

Submitted On: 2026-03-15 09:34:12

#include <bits/stdc++.h>
using namespace std;
#define ll long long
ll dp[51][51][51][3];
const int mod = 1e9+7;
int main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    int n; cin >> n;
    int A, B, C; cin >> A >> B >> C;
    ll sum = 0;
    for (int first = 0; first < 3; ++first) {
        if (first == 0 && !A) continue;
        if (first == 1 && !B) continue;
        if (first == 2 && !C) continue;
        memset(dp, 0, sizeof(dp));
        int a = A, b = B, c = C;
        if (first == 0) a--;
        else if (first == 1) b--;
        else if (first == 2) c--;
        dp[a][b][c][first]++;

        for (int i = a; i >= 0; --i) {
            for (int j = b; j >= 0; --j) {
                for (int k = c; k >= 0; --k) {
                    for (int last = 0; last < 3; ++last) {
                        if (last == 0 && i > 0) dp[i-1][j][k][last] += dp[i][j][k][1] + dp[i][j][k][2];
                        if (last == 1 && j > 0) dp[i][j-1][k][last] += dp[i][j][k][0] + dp[i][j][k][2];
                        if (last == 2 && k > 0) dp[i][j][k-1][last] += dp[i][j][k][0] + dp[i][j][k][1];
                        dp[i][j][k][last] %= mod;
                    }
                }
            }
        }

        for (int i = 0; i < 3; ++i) {
            if (i == first) continue;
            sum += dp[0][0][0][i];
            sum %= mod;
        }
    }
    cout << sum;

    return 0;
}