oj.uz

Submission #490496

# Submission time Handle Problem Language Result Execution time Memory
490496 2021-11-27T16:23:19 Z Yazan_Alattar Kangaroo (CEOI16_kangaroo) C++14
100 / 100
 153 ms 126016 KB 
#include <iostream>
#include <fstream>
#include <vector>
#include <cstring>
#include <algorithm>
#include <set>
#include <map>
#include <queue>
#include <list>
#include <utility>
#include <cmath>
#include <numeric>
using namespace std;
typedef long long ll;
#define F first
#define S second
#define pb push_back
#define endl "\n"
#define all(x) x.begin(), x.end()
const int M = 2007;
const ll inf = 1e18;
const ll mod = 1e9 + 7;
const double pi = acos(-1);
const int dx[] = {1, 0, -1, 0}, dy[] = {0, 1, 0, -1};

ll n, st, en, dp[M][M][2][2];

int main()
{
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n >> st >> en;
    dp[0][0][0][0] = 1;
    for(int i = 1; i <= n; ++i){
        for(int j = 1; j <= n; ++j){
            for(int on1 = 0; on1 < 2; ++on1){
                for(int on2 = 0; on2 < 2; ++on2){
                    if(i == st){
                        if(on1) continue;
                        dp[i][j][1][on2] = (dp[i - 1][j][0][on2] + dp[i - 1][j - 1][0][on2]) % mod;
                    }
                    else if(i == en){
                        if(on2) continue;
                        dp[i][j][on1][1] = (dp[i - 1][j][on1][0] + dp[i - 1][j - 1][on1][0]) % mod;
                    }
                    else{
                        dp[i][j][on1][on2] = (dp[i - 1][j - 1][on1][on2] * (j - on1 - on2)) % mod;
                        dp[i][j][on1][on2] += (dp[i - 1][j + 1][on1][on2] * j) % mod;
                    }
                }
            }
        }
    }
    cout << dp[n][1][1][1] << endl;
    return 0;
}
// Don't forget special cases. (n = 1?)
// Look for the constraints. (Runtime array? overflow?)

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 1 ms 344 KB Output is correct
4 Correct 1 ms 460 KB Output is correct
5 Correct 0 ms 464 KB Output is correct
6 Correct 1 ms 472 KB Output is correct
7 Correct 0 ms 472 KB Output is correct
8 Correct 1 ms 472 KB Output is correct
9 Correct 0 ms 456 KB Output is correct
10 Correct 1 ms 472 KB Output is correct
11 Correct 0 ms 472 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 1 ms 344 KB Output is correct
4 Correct 1 ms 460 KB Output is correct
5 Correct 0 ms 464 KB Output is correct
6 Correct 1 ms 472 KB Output is correct
7 Correct 0 ms 472 KB Output is correct
8 Correct 1 ms 472 KB Output is correct
9 Correct 0 ms 456 KB Output is correct
10 Correct 1 ms 472 KB Output is correct
11 Correct 0 ms 472 KB Output is correct
12 Correct 3 ms 2264 KB Output is correct
13 Correct 2 ms 2136 KB Output is correct
14 Correct 2 ms 2264 KB Output is correct
15 Correct 2 ms 2392 KB Output is correct
16 Correct 2 ms 2376 KB Output is correct
17 Correct 2 ms 2392 KB Output is correct
18 Correct 2 ms 2008 KB Output is correct
19 Correct 3 ms 2252 KB Output is correct
20 Correct 2 ms 2388 KB Output is correct

Subtask #4
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 344 KB Output is correct
3 Correct 1 ms 344 KB Output is correct
4 Correct 1 ms 460 KB Output is correct
5 Correct 0 ms 464 KB Output is correct
6 Correct 1 ms 472 KB Output is correct
7 Correct 0 ms 472 KB Output is correct
8 Correct 1 ms 472 KB Output is correct
9 Correct 0 ms 456 KB Output is correct
10 Correct 1 ms 472 KB Output is correct
11 Correct 0 ms 472 KB Output is correct
12 Correct 3 ms 2264 KB Output is correct
13 Correct 2 ms 2136 KB Output is correct
14 Correct 2 ms 2264 KB Output is correct
15 Correct 2 ms 2392 KB Output is correct
16 Correct 2 ms 2376 KB Output is correct
17 Correct 2 ms 2392 KB Output is correct
18 Correct 2 ms 2008 KB Output is correct
19 Correct 3 ms 2252 KB Output is correct
20 Correct 2 ms 2388 KB Output is correct
21 Correct 18 ms 16544 KB Output is correct
22 Correct 18 ms 18392 KB Output is correct
23 Correct 18 ms 21184 KB Output is correct
24 Correct 120 ms 125932 KB Output is correct
25 Correct 153 ms 126016 KB Output is correct
26 Correct 118 ms 125900 KB Output is correct
27 Correct 127 ms 125548 KB Output is correct
28 Correct 72 ms 76568 KB Output is correct