sk
sk#include<iostream>
#include<math.h>
using namespace std;
int main( )
{
int i,j,n,powe,arr[50];
int sum;
cout<<"enter no. of element in array \n";
cin>>n;
powe=pow(2,n-1);
cout<<"enter array \n";
for(i=0;i<n;i++)
{cin>>arr[i];}
for(i=0;i<n;i++)
{
sum+=(arr[i])*(powe);
}
cout<<sum;
return 0;
}