Submission #1189585

#	Time	Username	Problem	Language	Result	Execution time	Memory
1189585		c0det1ger	Tents (JOI18_tents)	C++20	100 / 100	52 ms	71236 KiB

tents

#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops,inline")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,avx,avx2,popcnt")
using namespace std;

#define int long long
#define double long double
#define codetiger_orz cin.tie(0);cin.sync_with_stdio(0);

signed main() {
    codetiger_orz
    
    int r, c;
    cin >> r >> c;
    const int mod = 1000000007;
    vector<vector<int>> dp(r + 1, vector<int>(c + 1, 1));
    for (int i = 1; i <= r; i++){
        for (int j = 1; j <= c; j++){
            dp[i][j] = dp[i - 1][j] + 4 * j * dp[i - 1][j - 1];
            if (i != 1){
                dp[i][j] += (i - 1) * j * dp[i - 2][j - 1];
            }
            if (j != 1){
                dp[i][j] += j * (j - 1) / 2 * dp[i - 1][j - 2];
            }
            dp[i][j] %= mod;
        }
    }
    cout << (dp[r][c] + mod - 1) % mod << "\n";
}

/*
 ____   ___    ___     ____  _____          ____    ____   ___
|      |   |  |   \   |        |     /|    |       |      |   \
|      |   |  |    |  |____    |      |    |   _   |____  |___/
|      |   |  |    |  |        |      |    |    |  |      |  \
|____  |___|  |___/   |____    |    __|__  |____|  |____  |   \
 
*/

• Subtask 1: 48 / 48
• Subtask 2: 52 / 52