C++ Return Binary from 1-256

#include "stdafx.h"
#include <iostream>

using namespace std;

int binary(int x) {
int arr[99], mod, quo, i = 1, ctr = 0, sum = 0;
do {
mod = x % 2;
arr[ctr] = mod;
quo = x / 2;
x = quo;

arr[ctr] *= i;
sum += arr[ctr];
ctr++;
i *= 10;
} while (x != 0);
return sum;
}

int main() {
int arr[256], index = 0;
for (int i = 1; i <= 256; i++) {
arr[index] = binary(i);
index++;
}
for (index = 0; index < 256; index++) {
// output
cout << index+1 << ": " << arr[index] << endl;
}

cin.get();
return 0;
}

Output