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Submission #452110

# Submission time Handle Problem Language Result Execution time Memory
452110 2021-08-03T19:32:39 Z JovanB Tents (JOI18_tents) C++17
100 / 100
 416 ms 31988 KB 
#include <bits/stdc++.h>
using namespace std;
 
const int MOD = 1000000007;
 
typedef long long ll;
 
int add(int a, int b){
    return (a+b)%MOD;
}
 
int mul(int a, int b){
    return ((ll)a*b)%MOD;
}
 
int pw(int a, int b){
    if(b == 0) return 1;
    int res = pw(a, b/2);
    res = mul(res, res);
    if(b%2) res = mul(res, a);
    return res;
}
 
int inv[3005];
int fact[3005];
int dp[3005][3005];
 
int bin(int n, int k){
    if(n < 0 || k < 0 || n < k) return 0;
    int res = fact[n];
    res = mul(res, inv[n-k]);
    res = mul(res, inv[k]);
    return res;
}
 
int solve(int h, int w){
    if(h < 0 || w < 0) return 0;
    if(h == 0 || w == 0) return 1;
    if(dp[h][w]) return dp[h][w];
    /// hor. par
    dp[h][w] = add(dp[h][w], mul(solve(h-1, w-2), w*(w-1)/2));
    /// ver. par
    dp[h][w] = add(dp[h][w], mul(solve(h-2, w-1), mul(w, h-1)));
    /// samo jedan
    dp[h][w] = add(dp[h][w], mul(4, mul(solve(h-1, w-1), w)));
    /// nista
    dp[h][w] = add(dp[h][w], solve(h-1, w));
    return dp[h][w];
}
 
int main(){
    ios_base::sync_with_stdio(false);
 
    fact[0] = inv[0] = 1;
    for(int i=1; i<=3000; i++){
        fact[i] = mul(fact[i-1], i);
        inv[i] = pw(fact[i], MOD-2);
    }
    int h, w;
    cin >> h >> w;
    cout << add(solve(h, w), MOD-1);
    return 0;
}

Subtask #1
48.0 / 48.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 460 KB Output is correct
4 Correct 2 ms 1152 KB Output is correct
5 Correct 2 ms 588 KB Output is correct
6 Correct 3 ms 1228 KB Output is correct
7 Correct 2 ms 724 KB Output is correct
8 Correct 3 ms 1356 KB Output is correct
9 Correct 2 ms 844 KB Output is correct
10 Correct 4 ms 1612 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Correct 5 ms 1740 KB Output is correct

Subtask #2
52.0 / 52.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 460 KB Output is correct
4 Correct 2 ms 1152 KB Output is correct
5 Correct 2 ms 588 KB Output is correct
6 Correct 3 ms 1228 KB Output is correct
7 Correct 2 ms 724 KB Output is correct
8 Correct 3 ms 1356 KB Output is correct
9 Correct 2 ms 844 KB Output is correct
10 Correct 4 ms 1612 KB Output is correct
11 Correct 1 ms 336 KB Output is correct
12 Correct 5 ms 1740 KB Output is correct
13 Correct 1 ms 344 KB Output is correct
14 Correct 7 ms 9676 KB Output is correct
15 Correct 305 ms 29216 KB Output is correct
16 Correct 4 ms 1484 KB Output is correct
17 Correct 26 ms 4920 KB Output is correct
18 Correct 58 ms 9280 KB Output is correct
19 Correct 345 ms 30888 KB Output is correct
20 Correct 245 ms 25412 KB Output is correct
21 Correct 128 ms 16064 KB Output is correct
22 Correct 168 ms 19968 KB Output is correct
23 Correct 128 ms 19484 KB Output is correct
24 Correct 416 ms 31988 KB Output is correct
25 Correct 303 ms 27128 KB Output is correct
26 Correct 362 ms 29768 KB Output is correct
27 Correct 408 ms 31044 KB Output is correct