codeforces 313C. Ilya and Matrix

#include <stdlib.h>

#include <string.h>

#include <stdio.h>

#include <ctype.h>

#include <math.h>

#include <stack>

#include <queue>

#include <map>

#include <set>

#include <vector>

#include <string>

#include <iostream>

#include <algorithm>

using namespace std;

#define ll long long

#define ls rt<<1

#define rs ls1

#define lson l,mid,ls

#define rson mid+1,r,rs

#define middle (l+r)>>1

#define eps (1e-9)

#define clr_all(x,c) memset(x,c,sizeof(x))

#define clr(x,c,n) memset(x,c,sizeof(x[0])*(n+1))

#define MOD 1000000007

#define inf 100000007

#define pi acos(-1.0)

#define M 2000000+5

int a[M];

int main(){

int n,i,j,t;

long long sum;

while(~scanf("%d",&n)){

sum=0;

for(i=0;i<n;i++)scanf("%d",&a[i]);

sort(a,a+n);

for(i=1;i<=n;i+=3*i)

for(j=n-i;j<n;j++)

sum+=a[j];

printf("%I64d\n",sum);

}

return 0;

}