Submission #527360

#	Time	Username	Problem	Language	Result	Execution time	Memory
527360		siewjh	Calvinball championship (CEOI15_teams)	C++17	100 / 100	95 ms	604 KiB

teams

#include <iostream>
#include <vector>
#include <algorithm>
#include <cstring>
using namespace std;
typedef long long ll;
const ll mod = 1'000'007;
int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	int nums;  cin >> nums;
	vector<int> vec(nums + 1), pmax(nums + 1, 0);
	for (int i = 1; i <= nums; i++) {
		cin >> vec[i];
		pmax[i] = max(pmax[i - 1], vec[i]);
	}
	vector<vector<ll>> memo(2, vector<ll>(nums + 1, 0));
	bool prev = 0;
	for (int i = 1; i < nums; i++) memo[0][i] = 1;
	ll ans = 0;
	for (int i = nums; i >= 1; i--) {
		ans += (memo[prev][pmax[i - 1]] * (vec[i] - 1)) % mod;
		ans %= mod;
		for (int j = 1; j < i; j++) memo[1 - prev][j] = (j * memo[prev][j] + memo[prev][j + 1]) % mod;
		prev = 1 - prev;
	}
	cout << (ans + 1) % mod;
	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