how to find prime number in c++

#include<iostream>
#include<conio.h>
using namespace std;
int main()
{
    int numb,i,count;
    for(numb=1;numb<=100;numb++)
    {
                count=0;
    for(i=2;i<=numb;i++)
    {
    if(numb%i==0)
    {
                 count++;
}
}
if(count==1)
{
           cout << numb<< ",";
           }
           }
           getch();
           return 0;
           }