从键盘输入任意正整数，判断是否素数的c语言

---

#include"math.h"
main()
{
int m,i,k;
scanf("%d",&m);
k=sqrt(m);
for(i=2;i<=k;i++)
if(m%i==0)break;
if(i>=k+1)printf("蚂州%d is a prime number\n",m);
else printf("%d is not a prime number\伏扰n"闷厅蔽,m);
}

---

最简单的源程序如下：
main()
{
int x;
printf("please enter a zhen number:")
scanf("%d",&x);
if(ss(x)) printf("%d是素凯培数\n",x);
else printf("不是素数袭明\拍孙告n");
}
int ss(int n)
{
int k;
for (k=2;k if (n%k==0)
return 0;
return 1;
}

---

#include
void main()
{ int a;
printf("请输入一个大于1的正整数：");
scanf("%d",&a);
while(a<=1)
{ cout<<困猛"数据错误，请重新汪察桥输入一个大于1的正整数：";
cin>>a;
}
void sushu(int);
sushu(a);
}

void sushu(int x)
{ int y=1,i;
for(i=2;i { if(x%i==0)
{ y=0;
break;
}
}
if(y==1)cout< else cout<}

---

#include

int isPrime(int n)
{
int i = 2;
for( ; i * i <= n; i = (i + 1) | 1)
if(n % i == 0)
return 0;
return n > 1;
}

int main(void)
{
int n;
scanf("带友%d", &n);
if(isPrime(n))
printf("%d is prime.\消行卖拿逗n", n);
else
printf("%d is not prime.\n", n);
return 0;
}

---

#include "stdio.h"
#include "源弊math.h"
int f(int a);
main()
{
int m;
scanf("%d"雹迟族,&m);
if(f(m)) printf("%d是素数\n"旦衫,m);
else printf("不是素数\n");
}
int f(int a)
{
int y,i;
for(i=2;i{
if(a%i==0) {y=0;break;}
else y=1;
}
return y;
}

//VC中调试通过!

---