Cod sursă (job #395103)

#include <fstream>
#include<algorithm>
using namespace std;
int a[100002];
int main()
{
    ifstream fin("lanterna.in");
    ofstream fout ("lanterna.out");
    int n, i, t1, t2;
    long long timp=0;
    fin>>n;
    for(i=1; i<=n; i++)
     fin>>a[i];
    sort(&a[1], &a[n+1]);
    while(n>3){
     t1=2*a[2]+a[1]+a[n];
     t2=a[n]+2*a[1]+a[n-1];
     if(t1<t2)
          timp=timp+t1;
     else
          timp=timp+t2;
     n=n-2;
    }
    if(n==2)
          timp=timp+a[2];
     else
          timp=timp+a[1]+a[2]+a[3];
    fout<<timp;
    return 0;
}