Submission #1167152

#	Time	Username	Problem	Language	Result	Execution time	Memory
1167152		Ludissey	Calvinball championship (CEOI15_teams)	C++20	10 / 100	60 ms	131072 KiB

teams

#include <bits/stdc++.h>
#define int long long
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
using namespace std;

const int MOD=1e9+7;

signed main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    int n; cin >> n;
    vector<vector<int>> dp(n,vector<int>(n,0));
    dp[0][0]=1;
    for (int i = 1; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            dp[i][j]=(dp[i-1][j]*(j+1))%MOD;
            if(j>0) dp[i][j]=(dp[i][j]+dp[i-1][j-1])%MOD;
        }
    }
    vector<int> a(n);
    for (int i = 0; i < n; i++) cin >> a[i];
    int mx=1;
    int sm=1;
    for (int i = 1; i < n-1; i++) {
        int nsm=0;
        for (int j = 0; j < n; j++)
        {
            nsm=(nsm+dp[(n-i)-2][j])%MOD;
        }
        nsm=(nsm*(a[i]-1))%MOD;
        nsm=(nsm*(mx+1))%MOD;
        if(a[i]==1) continue;
        mx=max(a[i],mx);
        sm=(sm+(nsm%MOD))%MOD;
    }
    sm=(sm+a[n-1]-1)%MOD;
    cout << sm << "\n";
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10