Cod sursă (job #112469)

#include <stdio.h>
#include <algorithm>
using namespace std;
FILE *fin ,*fout;
int a[100001];
int main()
{
    int n ,i ;
    long long t=0;
    fin = fopen("lanterna.in" ,"r");
    fout = fopen("lanterna.out" ,"w");
    fscanf(fin ,"%d" ,&n);
    for(i=1;i<=n;i++)
    {
        fscanf(fin ,"%d" ,&a[i]);
    }
    sort(a+1 ,a+n+1);
    while(n-2>=2)
    {
        if(a[1]+2*a[2]+a[n] <= a[1]+a[n]+a[n-1]) t+=(a[1]+2*a[2]+a[n]);
        else t+=(a[1]+a[n]+a[n-1]);
        n-=2;
    }
    if(n==3)
    {
        t+=(a[1]+a[2]+a[3]);
    }
    if(n==2)
    {
        t+=a[2];
    }
    fprintf(fout ,"%lld" , t);
    return 0;
}