Question

I think that my code works. However, it outputs 01111E5, or 17B879DD, or something like that.

Can someone please tell me why.

I am aware that I set the limit of P instead of 10,001. My code is like that because I start with 3, skipping the prime number 2.

#include <iostream>
bool prime (int i)
{
bool result = true;
int isitprime = i;
for(int j = 2; j < isitprime; j++)              ///prime number tester
{
    if(isitprime%j == 0) result = false;
}   
return result;
}


int main (void)
{
using namespace std;
int PrimeNumbers = 1;
int x = 0;
for (int i = 3 ; PrimeNumbers <=10000; i++)
{
    if(prime(i))
    {
        int prime = i;
        PrimeNumbers +=1;
    }
}   
cout<<prime<<endl;
system ("pause");
return 0;
}

Answer 1

The output isn’t strange at all.

cout<<prime<<endl;

You’re printing the function pointer of prime here.

You were probably intending to print the variable you create here:

 int prime = i;

But this is in the loop scope. In fact, if you compile with warnings enabled, your compiler should tell you that this variable is never used. Also, it’s bad practice to give variables in C or C++ the same name as functions (or any other variable in a higher level scope).