Submission #37363

#	Time	Username	Problem	Language	Result	Execution time	Memory
37363		cheater2k	Calvinball championship (CEOI15_teams)	C++14	100 / 100	736 ms	2668 KiB

teams

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

const int N = 10005;
const int md = 1000007;

int n, a[N], b[N], dp[2][N], ans;
vector< pair<int,int> > vec[N];

void add(int &x, int y) {
	x += y; while(x >= md) x -= md; if (x < 0) x += md;
}

int main() {
	scanf("%d", &n);
	int mx = 0;
	for (int i = 1; i <= n; ++i) {
		scanf("%d", &a[i]);
		int cur = min(a[i] - 1, mx);
		b[i] = mx;
		mx = max(mx, a[i]);
		a[i] = cur;
		vec[b[i]].push_back(make_pair(a[i], n - i));
	}
	// + a[i] * dp[n - i][b[i]]

	dp[n & 1][0] = 1;
	for (int i = 1; i <= n; ++i) dp[n & 1][i] = 1LL * dp[n & 1][i - 1] * n % md;

	for (int ngroup = n - 1; ngroup >= 1; --ngroup) {
		int t = ngroup & 1;
		int cur = 1;
		dp[t][0] = 1;
		for (int i = 1; i <= n; ++i) {
			cur = ((1LL * cur * ngroup) + dp[t ^ 1][i - 1]) % md;
			dp[t][i] = cur;
			//printf("%d %d %d\n", ngroup, i, dp[t][i]);
		}
		for (auto it : vec[ngroup]) {
			add(ans, 1LL * it.first * dp[t][it.second] % md);
		}
	}

	printf("%d\n", (ans + 1) % md);
}

Compilation message (stderr)

teams.cpp: In function 'int main()':
teams.cpp:15:17: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &n);
                 ^
teams.cpp:18:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &a[i]);
                     ^

• 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