CodeForces 158DIce Sculptures

#include<stdio.h>
#include<iostream>
#include<string.h>
#include<algorithm>
using namespace std;
int a[100500];
int main()
{
    int n;
    while(~scanf("%d",&n)){
        int sum=0;
        for(int i=0;i<n;i++){
            scanf("%d",&a[i]);
            sum+=a[i];
        }
        int thesum=-9999999;
        for(int i=2;i<=n/3;i++){
            if(n%i==0){
            for(int k=0;k<i;k++){
                int tempsum=0;
                for(int j=k;j<n;j+=i){
                    tempsum+=a[j];
                }
                if(tempsum>thesum)
                    thesum=tempsum;
                //printf("thesum=%d\n",thesum);
            }
            }
        }
        if(thesum>sum)
            sum=thesum;
        printf("%d\n",sum);
    }
}