#include <iostream>
#include <fstream>
#include <algorithm>
 
 
#include <iostream>
 
unsigned long count = 1; // we assume 2 has been found.
unsigned long primeArr[3] = {0};
 
bool primeArrCanDiv(unsigned long n){
    for(unsigned long i = 0; i<count; i++){
        if(n%primeArr[i] == 0) return true;
    }
    primeArr[count] = n;
    return false;
}
 
 
int main(){
    unsigned long j=3;
    primeArr[0]=2;
    while(count<3){
        if(!primeArrCanDiv(j))
        {
            count++;
            std::cout << count << '\n';
        }
        ++j;
    }
    return 0;
}

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