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Submission #573588

# Submission time Handle Problem Language Result Execution time Memory
573588 2022-06-06T21:36:20 Z Hanksburger Boat (APIO16_boat) C++17
0 / 100
 248 ms 4344 KB 
#include <bits/stdc++.h>
#define int long long
using namespace std;
const int mod=1e9+7;
int dp[1005][505], inv[505], a[505], b[505], c[1005];
set<int> s;
int f(int x, int y)
{
    if (!y)
        return 1;
    int res=f(x, y/2);
    if (y&1)
        return res*res%mod*x%mod;
    else
        return res*res%mod;
}
signed main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n, m=0;
    cin >> n;
    for (int i=1; i<=n; i++)
        inv[i]=f(i, mod-2);
    for (int i=1; i<=n; i++)
    {
        cin >> a[i] >> b[i];
        s.insert(a[i]);
        s.insert(b[i]+1);
    }
    for (auto itr=s.begin(); itr!=s.end(); itr++)
        c[++m]=(*itr);
    for (int i=0; i<=n; i++)
        dp[0][i]=1;
    for (int i=1; i<m; i++)
    {
        for (int j=0; j<=n; j++)
        {
            dp[i][j]=dp[i-1][j];
//            cout << "--------- i j " << i << ' '  << j << ' ' << dp[i][j] << '\n';
            int num=1, cnt=0;
            for (int k=1; k<=j; k++)
            {
                if (a[j-k+1]<=c[i] && c[i+1]-1<=b[j-k+1])
                {
                    cnt++;
                    num=num*(c[i+1]-c[i]-cnt+1)%mod*inv[cnt]%mod;
                    dp[i][j]=(dp[i][j]+dp[i-1][j-k]*num)%mod;
                }
//                cout << "i j k " << i << ' ' << j << ' ' << k << ' ' << dp[i][j] << '\n';
            }
        }
    }
    cout << dp[m-1][n];
    return 0;
}

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Incorrect 248 ms 4344 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Incorrect 248 ms 4344 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 5 ms 1136 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Incorrect 248 ms 4344 KB Output isn't correct
2 Halted 0 ms 0 KB -