Submission #527228

#	Time	Username	Problem	Language	Result	Execution time	Memory
527228		joelau	Calvinball championship (CEOI15_teams)	C++14	100 / 100	413 ms	656 KiB

teams

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

long long N, A[10005], dp[2][10005], most[10005], p = 1000007;

int main() {
    ios_base::sync_with_stdio(false); cin.tie(NULL);
    cin >> N;
    most[0] = 0;
    for (long long i = 1; i <= N; ++i) {
        cin >> A[i];
        most[i] = max(most[i-1],A[i]);
    }
    for (long long i = 1; i <= N+1; ++i) dp[1][i] = 1;
    long long ans = 1;
    for (long long i = N; i > 0; --i) {
        for (long long j = 1; j <= i; ++j) dp[0][j] = (dp[1][j] * j + dp[1][j+1]) % p;
        ans = (ans + dp[1][most[i-1]] * min(most[i-1],A[i]-1)) % p;
        for (long long j = most[i-1]+1; j < A[i]; ++j) ans = (ans + dp[1][j]) % p;
        swap(dp[0],dp[1]);
    }
    cout << ans;

    return 0;
}

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