Submission #118752

#	Time	Username	Problem	Language	Result	Execution time	Memory
118752		silxikys	Calvinball championship (CEOI15_teams)	C++14	20 / 100	257 ms	544 KiB

teams

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const int maxn = 1e4+4, M = 1e9+7;
int n, a[maxn];
int dp[2][maxn];
int k[maxn];

void madd(int& a, int b) {
	a = (a+b) % M;
}
int mult(int a, int b) {
	return (1LL*a*b) % M;
}

int main()
{
    ios_base::sync_with_stdio(false); cin.tie(0);
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        k[i] = max(k[i-1],a[i-1]);
    }
    for (int i = 1; i <= n+1; i++) {
    	dp[0][i] = 1;
    }

    int ans = 0;
    for (int i = n; i >= 1; i--) {
    	for (int j = 1; j <= i; j++) {
    		dp[1][j] = (mult(j,dp[0][j]) + dp[0][j+1]) % M;
    	}
        if (k[i] < a[i]) {
            madd(ans,mult(k[i],dp[0][k[i]]));
        }
        else {
            madd(ans,mult(a[i]-1,dp[0][k[i]]));
        }

    	for (int j = 1; j <= n; j++) {
    		dp[0][j] = dp[1][j];
    	}
    }

    cout << ((ans+1)%M) << '\n';
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 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