Submission #628716

#	Time	Username	Problem	Language	Result	Execution time	Memory
628716		a_aguilo	Fancy Fence (CEOI20_fancyfence)	C++14	15 / 100	97 ms	1328 KiB

fancyfence

#include<bits/stdc++.h>

using namespace std;

int MOD = 1e9+7;

int main(){
    int n;
    cin >> n;
    vector<int> heights(n);
    vector<int> widths(n);
    for(int i = 1; i <= n; ++i) cin >> heights[n-i];
    for(int i = 1; i <= n; ++i) cin >> widths[n-i];
    long long int ans = 0;
    long long int W = 0;
    long long int H;
    for(int i = 0; i < n; ++i){
        W += widths[i];

        W%=MOD;
        long long chooseW = (W*(W+1)/2)%MOD;
        if(i == n-1) H = heights[i];
        else H = heights[i]- heights[i+1];
        long long chooseh = (H*(H+1)/2)%MOD;
        ans+= (chooseW*chooseh)%MOD;
        if(i != n-1){
            ans += (H*chooseW)%MOD;
        }
        ans%=MOD;
    }
    cout << ans << endl;
    return 0;
}

• Subtask 1: 0 / 0
• Subtask 2: 0 / 12
• Subtask 3: 0 / 13
• Subtask 4: 15 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27