Submission #335384

#	Time	Username	Problem	Language	Result	Execution time	Memory
335384		mehrdad_sohrabi	Tents (JOI18_tents)	C++14	100 / 100	312 ms	73580 KiB

tents

#include <bits/stdc++.h>
typedef long long int ll;
typedef long double ld;
#define pb push_back
#define pii pair < ll , ll >
#define F first
#define S second
#define endl '\n'
#define int long long
#define sync ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
#define kill(x) return cout<<x<<'\n', 0;
using namespace std;
const int N=3e3+100;
ll dp[N][N];
ll mod=1e9+7;
int32_t main(){
    ll n,m;
    cin >> n >> m;
    dp[0][0]=1;
    for (int i=1;i<N;i++) dp[0][i]=1,dp[i][0]=1;
    for (int i=1;i<=n;i++){
        for (int j=1;j<=m;j++){
            dp[i][j]=dp[i][j-1]+dp[i-1][j-1]*4*i%mod;
            if (i>=2) dp[i][j]+=dp[i-2][j-1]*(i*(i-1)/2)%mod;
            if (j>=2) dp[i][j]+=dp[i-1][j-2]*i*(j-1)%mod;
            dp[i][j]%=mod;
        }
    }
    cout << dp[n][m]-1 << endl;

}

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