C編寫的吧?
#include "stdafx.h"
#include "math.h"
int main()
{
int n,i;
printf("請輸入一個數(shù)");
scanf("%d",&n);
if((n==2)) printf("%d是素數(shù)",n);
else
{
for(i=2;i=sqrt(n) printf("%d是素數(shù)",n);
}
return 0;
}