Pizzeria

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <set>
#include <iomanip>

#define uint unsigned int
#define INF 999999999
#define ll long long
#define M 1000000007
#define E 0.0000001
#define N 131072

using namespace std;

int main()
{
    cin.sync_with_stdio(false);
    cin.tie(0);

    int n;
    cin>>n;
    long long ans = 0;

    long long m = 1;
    for (int i = 1; i < n; i++) {
        m = (m<<1) % M;
    }

    for (int i = 0; i < n; i++) {
        long long x;
        cin>>x;
        ans = (ans + x * m) % M;
    }

    cout<<ans<<endl;

    return 0;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED