Submission #117646

#	Time	Username	Problem	Language	Result	Execution time	Memory
117646		minhtung0404	Calvinball championship (CEOI15_teams)	C++17	100 / 100	217 ms	640 KiB

teams

//https://oj.uz/problem/view/CEOI15_teams

#include<bits/stdc++.h>
const int N = 1e4 + 5;
const int mod = 1e6 + 7;
using namespace std;

int n, a[N], f[N], g[N], cur[N], ans;

void add(int&a, int b){
    a += b; if (a >= mod) a -= mod; if (a < 0) a += mod;
}

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> a[i];
        cur[i] = max(cur[i-1], a[i]);
    }
    for (int i = 0; i <= n; i++) f[i] = 1;
    for (int i = n; i >= 1; i--){
        add(ans, 1LL * f[cur[i-1]] * (a[i]-1) % mod);
        for (int j = 0; j <= n; j++) g[j] = (1LL * f[j] * j + f[j+1]) % mod;
        for (int j = 0; j <= n; j++) f[j] = g[j];
    }
    add(ans, 1);
    cout << ans;
}

• 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