Prime numbers

addprime = true;
for (checker = 1; checker <prime; checker++)
{
residu = prime%checker;
if(residu == 0 && checker != 1)addprime = false;
}

#include <iostream.h>
#include <math.h>

using namespace std;

int main(void){

int primelist[10000]={2,3};  //array to store all prime numbers
int pn=2;   //number of primes in array
int i;        //number to check if prime
int i2;      //index of prime list
bool prime;

for(i=5;i<10000;i+=2){
      for(i2=0,prime=true;primelist[i2]<=sqrt(i);i2++){
              if(i%primelist[i2]==0)prime=false;
      }
      if(prime){
              primelist[pn]=i;
              pn++;
      }
}

for(i=0;i<pn;i++)printf("%d\n",primelist[i]);

return 0;
}