oj.uz

Submission #312146

# Submission time Handle Problem Language Result Execution time Memory
312146 2020-10-12T13:35:07 Z hoangtung_pro Kangaroo (CEOI16_kangaroo) C++14
100 / 100
 29 ms 31872 KB 
#include<bits/stdc++.h>

#define endl '\n'
#define fi first
#define se second
#define pb push_back
#define bit(s, i) (s & (1<<i))

using namespace std;

const int maxn = 2005;
const int mod = 1e9+7;

typedef long long ll;
typedef pair < int, int > ii;

int n, st, en;

ll dp[maxn][maxn];

int main()
{
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    //freopen(".inp","r",stdin);
    //freopen(".out","w",stdout);

    cin >> n >> st >> en;

    memset(dp, 0, sizeof dp);
    dp[0][0] = 1;

    for(int i=1;i<=n;++i)
    for(int j=1;j<=i;++j)
    {
        if(i == st || i == en)
        {
            dp[i][j] = (dp[i][j] + dp[i - 1][j - 1]) % mod;
            dp[i][j] = (dp[i][j] + dp[i - 1][j]) % mod;
//            cout << i << ' ' << j << ' ' << dp[i][j] << endl;
            continue;
        }

        ll cur = dp[i - 1][j + 1] * j;
        dp[i][j] = (dp[i][j] + cur) % mod;
        int x = j;
        if(st < i) -- x;
        if(en < i) -- x;
        cur = dp[i - 1][j - 1] * x;
        dp[i][j] = (dp[i][j] + cur) % mod;
//        cout << i << ' ' << j << ' ' << dp[i][j] << endl;
    }
    cout << dp[n][1];
}

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 31744 KB Output is correct
2 Correct 17 ms 31744 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 31744 KB Output is correct
2 Correct 17 ms 31744 KB Output is correct
3 Correct 18 ms 31872 KB Output is correct
4 Correct 17 ms 31744 KB Output is correct
5 Correct 17 ms 31744 KB Output is correct
6 Correct 17 ms 31744 KB Output is correct
7 Correct 17 ms 31744 KB Output is correct
8 Correct 18 ms 31744 KB Output is correct
9 Correct 18 ms 31744 KB Output is correct
10 Correct 17 ms 31744 KB Output is correct
11 Correct 18 ms 31744 KB Output is correct

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 31744 KB Output is correct
2 Correct 17 ms 31744 KB Output is correct
3 Correct 18 ms 31872 KB Output is correct
4 Correct 17 ms 31744 KB Output is correct
5 Correct 17 ms 31744 KB Output is correct
6 Correct 17 ms 31744 KB Output is correct
7 Correct 17 ms 31744 KB Output is correct
8 Correct 18 ms 31744 KB Output is correct
9 Correct 18 ms 31744 KB Output is correct
10 Correct 17 ms 31744 KB Output is correct
11 Correct 18 ms 31744 KB Output is correct
12 Correct 18 ms 31744 KB Output is correct
13 Correct 18 ms 31740 KB Output is correct
14 Correct 18 ms 31824 KB Output is correct
15 Correct 17 ms 31744 KB Output is correct
16 Correct 17 ms 31744 KB Output is correct
17 Correct 18 ms 31744 KB Output is correct
18 Correct 17 ms 31744 KB Output is correct
19 Correct 18 ms 31744 KB Output is correct
20 Correct 18 ms 31744 KB Output is correct

Subtask #4
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 31744 KB Output is correct
2 Correct 17 ms 31744 KB Output is correct
3 Correct 18 ms 31872 KB Output is correct
4 Correct 17 ms 31744 KB Output is correct
5 Correct 17 ms 31744 KB Output is correct
6 Correct 17 ms 31744 KB Output is correct
7 Correct 17 ms 31744 KB Output is correct
8 Correct 18 ms 31744 KB Output is correct
9 Correct 18 ms 31744 KB Output is correct
10 Correct 17 ms 31744 KB Output is correct
11 Correct 18 ms 31744 KB Output is correct
12 Correct 18 ms 31744 KB Output is correct
13 Correct 18 ms 31740 KB Output is correct
14 Correct 18 ms 31824 KB Output is correct
15 Correct 17 ms 31744 KB Output is correct
16 Correct 17 ms 31744 KB Output is correct
17 Correct 18 ms 31744 KB Output is correct
18 Correct 17 ms 31744 KB Output is correct
19 Correct 18 ms 31744 KB Output is correct
20 Correct 18 ms 31744 KB Output is correct
21 Correct 19 ms 31744 KB Output is correct
22 Correct 19 ms 31744 KB Output is correct
23 Correct 19 ms 31744 KB Output is correct
24 Correct 29 ms 31872 KB Output is correct
25 Correct 29 ms 31776 KB Output is correct
26 Correct 29 ms 31744 KB Output is correct
27 Correct 29 ms 31744 KB Output is correct
28 Correct 24 ms 31744 KB Output is correct