Submission #888126

# Submission time Handle Problem Language Result Execution time Memory
888126 2023-12-16T05:32:28 Z vjudge1 Tents (JOI18_tents) C++17
100 / 100
61 ms 72284 KB
#include <bits/stdc++.h>
using namespace std;

#pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
// Ofast, O0, O1, O2, O3, unroll-loops, fast-math, trapv

typedef long long ll;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;

#define Mp          make_pair
#define sep         ' '
#define endl        '\n'
#define F	        first
#define S	        second
#define pb          push_back
#define all(x)      (x).begin(),(x).end()
#define kill(res)	cout << res << '\n', exit(0);
#define set_dec(x)	cout << fixed << setprecision(x);
#define fast_io     ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define file_io     freopen("input.txt", "r", stdin) ; freopen("output.txt", "w", stdout);

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const ll N = 3e3 + 50;
const ll Mod = 1e9 + 7;

ll n, m, dp[N][N], inv2;

ll power(ll a, ll b, ll md = Mod){
    ll ans = 1;
    for(; b; b /= 2, a = a * a % md){
        if(b % 2) ans = ans * a % md;
    }
    return ans;
}

ll c2(ll x){
    return x * (x-1) % Mod * inv2 % Mod;
}

int main(){
    fast_io;

    inv2 = power(2, Mod-2);

    cin >> n >> m;

    dp[0][0] = 1;
    for(int i = 1; i <= n; i++) dp[i][0] = 1;
    for(int j = 1; j <= m; j++) dp[0][j] = 1;

    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            dp[i][j] = (dp[i-1][j] + 4 * dp[i-1][j-1] * j) % Mod;
            if(i > 1) dp[i][j] = (dp[i][j] + dp[i-2][j-1] * j * (i-1)) % Mod;
            if(j > 1) dp[i][j] = (dp[i][j] + dp[i-1][j-2] * c2(j)) % Mod;
        }
    }

    cout << (dp[n][m] - 1 + Mod) % Mod;

}
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 6492 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 6492 KB Output is correct
7 Correct 1 ms 2396 KB Output is correct
8 Correct 1 ms 6492 KB Output is correct
9 Correct 1 ms 4444 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 2 ms 8540 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 6492 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 6492 KB Output is correct
7 Correct 1 ms 2396 KB Output is correct
8 Correct 1 ms 6492 KB Output is correct
9 Correct 1 ms 4444 KB Output is correct
10 Correct 1 ms 8540 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 2 ms 8540 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 12 ms 55764 KB Output is correct
15 Correct 41 ms 68308 KB Output is correct
16 Correct 3 ms 6744 KB Output is correct
17 Correct 9 ms 16988 KB Output is correct
18 Correct 13 ms 29188 KB Output is correct
19 Correct 46 ms 70368 KB Output is correct
20 Correct 37 ms 59996 KB Output is correct
21 Correct 25 ms 41564 KB Output is correct
22 Correct 26 ms 53852 KB Output is correct
23 Correct 19 ms 72224 KB Output is correct
24 Correct 61 ms 72284 KB Output is correct
25 Correct 48 ms 64092 KB Output is correct
26 Correct 52 ms 68344 KB Output is correct
27 Correct 61 ms 70488 KB Output is correct