Prime Number Series

[jNU5fSEw]

//here is the code in C++ for outputting prime numbers below any user input integer
#include<iostream.h>
#include<math.h>
int PN(int num)
{
int div, prime;
prime=1;
div=2;
while (div<=sqrt(num) && prime==1)
{
if (num % div==0)
prime=0;
else
prime=1;
div++;
}
return(prime);
}
int main()
{
int x, d;
cout<<"end integer: ";
cin>>x;

d=2;
while (d<x+1)
{
if (PN(d)==1)
cout<<d<<endl;
d++;
}
}

[Welzevul]

//here is the code in C++ for outputting prime numbers below any user input integer
#include<iostream>
#include<math.h>


int PN(int num)
{
int div, prime;
prime=1;
div=3;
while (div<=sqrt((double)num) && prime==1)
{
if (num % div==0)
prime=0;
div+=2;//must take the odd number
}
return(prime);
}
int main()
{
int x, d;
std::cout<<"end integer: ";
std::cin>>x;

d=3;
if(x>=2)
std::cout<<"2\n";
while (d<=x)
{
if (PN(d)==1)
std::cout<<d<<'\n';
d+=2;//and here
}
}

[Scipio]

You can use the code-format (#-format on your right when posting) to upload code. And for testing primenumbers: http://en.wikipedia.org/wiki/Primality_test