Submission #1069102

#	Time	Username	Problem	Language	Result	Execution time	Memory
1069102		vjudge1	Calvinball championship (CEOI15_teams)	C++17	100 / 100	180 ms	676 KiB

teams

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

#define ff  first
#define ss  second
#define pb  push_back

const int N = 3e5 + 5;
const int mod = 1e6 + 7;
const int oo = 2e9;

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

int main() {
    #ifdef LOCAL
    freopen("input.txt","r",stdin);
    #endif // LOCAL

    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    int n; cin >> n;
    vector <int> a(n);
    for (auto &e : a) cin >> e;

    vector <int> ask (n, 0);
    for (int i = 2; i < n; ++i) {
        ask[i] = max(a[i - 2], ask[i - 1]);
    }

    vector <vector <int>> dp (2, vector<int>(n + 1, 0));
    vector <int> sv (n + 1, 0);

    sv[n]=1;
    for (int j = 1; j <= n; ++j) dp[n & 1][j] = 1;

    for (int i = n - 1; i >= 0; --i) {
        for (int j = 0; j < n; ++j) {
            dp[i & 1][j] = (1ll * dp[(i + 1) & 1][j] * j + dp[(i + 1) & 1][j + 1]) % mod;
        }
        sv[i] = dp[i & 1][ask[i]];
    }

    int ans = 0;
    for (int i = 0; i < n; ++i) {
        ans = (1ll * ans + 1ll * sv[i + 1] * (a[i] - 1)) % mod;
    }
    cout << (ans + 1)%mod << '\n';
}

• 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