제출 #110619

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
110619		someone_aa	Calvinball championship (CEOI15_teams)	C++17	100 / 100	273 ms	760 KiB

teams

#include <bits/stdc++.h>
#define ll long long
#define pb push_back
#define mp make_pair
using namespace std;
const int maxn = 11000;
const ll mod = 1000007LL;
ll dp[2][maxn];
ll a[maxn], n;
ll prefmax[maxn];


int main() {
    // dp[i][j] -> If we are given a sequence of arbitrary length and maximum element j,
    // on how many ways can we extend it if we can add exactly i elements
    cin>>n;
    prefmax[0] = 1LL;
    for(int i=1;i<=n;i++) {
        cin>>a[i];
        prefmax[i] = max(prefmax[i-1], a[i]);
    }

    for(int i=1;i<=n;i++) {
        dp[0][i] = 1LL;
    }

    ll result = 0LL;
    for(int i=n;i>=1;i--) {
        for(int j=1;j<=n;j++) {
            int d = n - i + 1;
            dp[d%2][j] = j*dp[(d-1)%2][j] + dp[(d-1)%2][j+1];
            dp[d%2][j] %= mod;
        }
        result += (a[i]-1)*(dp[(n-i)%2][prefmax[i-1]]);
        result %= mod;
    }
    cout<<(result+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