Submission #745782

#	Time	Username	Problem	Language	Result	Execution time	Memory
745782		vjudge1	Fancy Fence (CEOI20_fancyfence)	C++14	13 / 100	62 ms	3148 KiB

fancyfence

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

#define int long long

const int MOD = 1e9 +7;

int binpow(int a, int b){
    int ans = 1;
    while(b != 0){
        if(b & 1){
            ans = ans * a % MOD;
        }
        a = a * a % MOD;
        b /= 2;
    }
    return ans;
}

signed main() {
    int n;
    cin >> n;
    vector<int> h(n), w(n);
    int cnt = 0;
    for(int i = 0; i < n; i++){
        cin >> h[i];
    }
    for(int i = 0; i < n; i++){
        cin >> w[i];
    }
    int dv = binpow(2, MOD - 2);
    int egy = 0, ketto = 0;
    int ans = 0;
    for(int i = 0; i < n; i++){
        int act1, bn1, bn2;
        egy = (egy + w[i]) % MOD;
        if(h[i] == 1){
            ans = ans + (ketto * (ketto + 1) % MOD) % MOD;
            ketto = 0;
        }
        else{
            ketto = (ketto + w[i]) % MOD;
        }
    }
    ans = ans + (ketto * (ketto + 1) % MOD) % MOD;
    ans = (ans + (egy * (egy + 1) % MOD) * dv) % MOD;
    cout << ans << endl;
    return 0;
}

Compilation message (stderr)

fancyfence.cpp: In function 'int main()':
fancyfence.cpp:35:13: warning: unused variable 'act1' [-Wunused-variable]
   35 |         int act1, bn1, bn2;
      |             ^~~~
fancyfence.cpp:35:19: warning: unused variable 'bn1' [-Wunused-variable]
   35 |         int act1, bn1, bn2;
      |                   ^~~
fancyfence.cpp:35:24: warning: unused variable 'bn2' [-Wunused-variable]
   35 |         int act1, bn1, bn2;
      |                        ^~~
fancyfence.cpp:24:9: warning: unused variable 'cnt' [-Wunused-variable]
   24 |     int cnt = 0;
      |         ^~~

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