Submission #81971

#	Time	Username	Problem	Language	Result	Execution time	Memory
81971		Saboon	Calvinball championship (CEOI15_teams)	C++14	100 / 100	216 ms	1240 KiB

teams

#include <bits/stdc++.h>
#define F first
#define S second
#define PB push_back
#define PF push_front
#define MP make_pair
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
const int maxn = 1e4 + 10;
const int mod = 1e6 + 7;

ll pd[maxn], dp[3][maxn], par[maxn], a[maxn];

int main() {
	int n;
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> a[i];
		par[i] = max (par[i - 1], a[i]);
	}

	for (int i = 1; i <= n; i++)
		dp[0][i] = 1;
	pd[0] = 1;
	for (int i = 1; i <= n; i++) {
		int p = i % 2;
		for (int j = 1; j <= n; j++) {
			dp[p][j] = (1ll * j * dp[p^1][j] + dp[p^1][j + 1]) % mod;
		}
		pd[i] = dp[p][par[n - i - 1]];
	}
	ll ans = 0;
	for (int i = 1; i <= n; i++) {
		ans = (ans + 1ll * (a[i] - 1) * pd[n - i] % mod);
	}
	cout << (ans + 1) % mod << endl;
}

• 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