关于判断素数 !!!
#include "stdafx.h"
#include <math.h>
int isprime(int num)
{
int flag=1,i;
for(i=2;i<num/2;i++)
if(num%i==0)
flag=0;
return(flag);
}
int _tmain(int argc, _TCHAR* argv[])
{
int n;
printf("input an integer:");
scanf_s("%d",&n);
if(isprime(n));
printf("%d is a prime ",n);
else
printf("%d is not a prime ",n);
printf("\n");
????????