Print prime number program in C++

#include <iostream>
#include<cmath>
using namespace std;

int main()
{
    cout << "Prime Numbers between 1 and 100 are:\n";

    for(int i = 2; i <= 100; ++i) //loop to check for each number in the range
    {
        int ctr = 0; //to maintain factor count

        for(int j = 2; j <= sqrt(i); ++j) //checking for factors
        {
            if(i % j == 0)
            {
                ctr = 1; //increasing factor count when found
            }
        }

        if(ctr == 0) //checking and printing prime numbers
        {
            cout << i << " ";
        }
    }

    return 0;
}

Output:

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97