Submission #1253975

#	Time	Username	Problem	Language	Result	Execution time	Memory
1253975		nerrrmin	Flooding Wall (BOI24_wall)	C++20	12 / 100	34 ms	8264 KiB

Main

#include<bits/stdc++.h>
#define endl '\n'
#define pb push_back
using namespace std;
const int maxn = 5e5 + 10;
void speed()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
}
int n, a[maxn], b[maxn];
long long p[maxn];
const long long mod = 1e9+7;
int main()
{
    speed();

    cin >> n;
    for (int i = 1; i <= n; ++ i)
    {
        cin >> a[i];
    }
    for (int i = 1; i <= n; ++ i)
        cin >> b[i];

        p[0] = 1;
    for (int i = 1; i <= n; ++ i)
    {
        p[i] = p[i-1] * 2;
        p[i] %= mod;
    }
        long long ans = 0;
    for (int i = 2; i <= n-1; ++ i)
    {
        int lt = i-1;
        int rt = n - i;
        ans += 1LL * (p[lt] - 1) * 1LL * (p[rt] - 1);
        ans %= mod;
    }
    cout << ans << endl;
    return 0;
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 17
• Subtask 3: 0 / 19
• Subtask 4: 0 / 14
• Subtask 5: 12 / 12
• Subtask 6: 0 / 30