Submission #888180

# Submission time Handle Problem Language Result Execution time Memory
888180 2023-12-16T09:46:44 Z Shayan86 Tents (JOI18_tents) C++14
100 / 100
64 ms 72536 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 348 KB Output is correct
2 Correct 1 ms 396 KB Output is correct
3 Correct 1 ms 2392 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 348 KB Output is correct
2 Correct 1 ms 396 KB Output is correct
3 Correct 1 ms 2392 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 1 ms 600 KB Output is correct
14 Correct 10 ms 55848 KB Output is correct
15 Correct 45 ms 68184 KB Output is correct
16 Correct 3 ms 6488 KB Output is correct
17 Correct 9 ms 16984 KB Output is correct
18 Correct 15 ms 29284 KB Output is correct
19 Correct 46 ms 70236 KB Output is correct
20 Correct 37 ms 59996 KB Output is correct
21 Correct 25 ms 41564 KB Output is correct
22 Correct 27 ms 53852 KB Output is correct
23 Correct 20 ms 72284 KB Output is correct
24 Correct 62 ms 72536 KB Output is correct
25 Correct 47 ms 64092 KB Output is correct
26 Correct 64 ms 68184 KB Output is correct
27 Correct 60 ms 70388 KB Output is correct