Submission #28635

#	Time	Username	Problem	Language	Result	Execution time	Memory
28635		rondojim	Calvinball championship (CEOI15_teams)	C++14	100 / 100	116 ms	2184 KiB

teams

#include <bits/stdc++.h>
 
using namespace std;
 
const int MOD = 1000000 + 7;
const int NMAX = 10000 + 5;
 
int N;
int v[NMAX];
int dp[2][NMAX];
 
bool freq[NMAX];
int col[NMAX];
 
int main()
{
    cin >> N;
    for (int i = 1; i <= N; ++ i)
        cin >> v[i];
 
    col[0] = 0;
    for (int i = 1; i <= N; ++ i) {
        col[i] = col[i - 1];
        if (!freq[v[i]]) {
            freq[v[i]] = true;
            ++ col[i];
        }
    }
 
    int ans = 1;
    for (int i = N; i; -- i) {
        if (i == N) {
            for (int col = 1; col <= N; ++ col)
                dp[N & 1][col] = 1;
        }
        else {
            for (int col = 0; col <= i; ++ col)
                dp[i & 1][col] = (dp[(i + 1) & 1][col + 1] + 1LL * col * dp[(i + 1) & 1][col]) % MOD;
        }
        ans = (ans + dp[i & 1][col[i - 1]] * (v[i] - 1LL)) % MOD;
    }
    cout << ans << '\n';
    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