Problem:
Score : 700 points

Problem Statement

We have N gemstones labeled 1 through N.

You can perform the following operation any number of times (possibly zero).

Select a positive integer x, and smash all the gems labeled with multiples of x.

Then, for each i, if the gem labeled i remains without getting smashed, you will receive a_i yen (the currency of Japan).
However, a_i may be negative, in which case you will be charged money.

By optimally performing the operation, how much yen can you earn?

Constraints

All input values are integers.

1 \leq N \leq 100

|a_i| \leq 10^9

Input

Input is given from Standard Input in the following format:

N
a_1 a_2 ... a_N

Output

Print the maximum amount of money that can be earned.

Sample Input 1

6
1 2 -6 4 5 3

Sample Output 1

12

It is optimal to smash Gem 3 and 6.

Sample Input 2

6
100 -100 -100 -100 100 -100

Sample Output 2

200

Sample Input 3

5
-1 -2 -3 -4 -5

Sample Output 3

0

It is optimal to smash all the gems.

Sample Input 4

2
-1000 100000

Sample Output 4

99000

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include <iostream>
#include <vector>
#include <string>
#include <queue>
#include "cmath"
using namespace std;

int main(int argc, const char * argv[]) {
    int n;
    cin >>n;
    vector<int> v(n+1,0);
    for (int i=0; i<n; i++) {
        cin>>v[i+1];
    }
    for (int j=n; j>=1; j--) {
        long long score=0;
        vector<int> tmp;
        int hoge=1;
        while (1) {
            if (hoge*j <=n ) {
                tmp.push_back(hoge*j);
                hoge++;
            }
            else break;
        }
        for(auto it:tmp) score+=v[it];
        if (score<0) {
            for(auto it:tmp) v[it]=0;
        }
    }
    long long sum=0;
    for(auto it:v) sum+=it;
    cout<<sum<<endl;
    return 0;
}