Submission #403654

#	Time	Username	Problem	Language	Result	Execution time	Memory
403654		saleh	Calvinball championship (CEOI15_teams)	C++17	100 / 100	442 ms	1092 KiB

teams

#include <bits/stdc++.h>


using namespace std;


const int MAXN = 10 * 1000 + 23, D = 1000 * 1000 + 7;















int dp[2][MAXN], a[MAXN], n, cnt[MAXN], jav;



int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr), cout.tie(nullptr);
	cin >> n;
	for (int i = 0; i < n; i++) cin >> a[i];
	{
		set<int> s;
		for (int i = 0; i < n; i++) {
			s.insert(a[i]);
			cnt[i] = s.size();
		}
	}
	fill(dp[1], dp[1] + n, 1);
	for (int i = 0; i < n - 1; i++) {
		for (int j = 1; j < n - 1; j++) dp[i & 1][j] = (1ll * dp[1 - (i & 1)][j] * j % D + dp[1 - (i & 1)][j + 1]) % D;
		int j = n - i - 1;
		jav += 1ll * (a[j] - 1) * dp[1 - (i & 1)][cnt[j - 1]] % D;
		jav %= D;
	}
	cout << (jav + 1) % D;
	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