一道c语言的基础题望大家看看

感觉自己是个憨憨，望各位帮忙看看，蟹蟹各位潜水专家，感谢解答，感谢回答，感谢解答

#include <stdio.h>
int main()
{
    int i,n;
    while(1)
    {
        printf("Input a number(>0):");
        scanf("%d",&n);
        if(n<2)
            printf("%d is not a prime number\n",n);
        else
        {
            for(i=2;i<n;i++)
            {
                if(n%i==0)
                    break;
            }
            if(i==n)
            {
                printf("%d is a prime number\n",n);
                break;
            }else
                printf("%d is not a prime number\n",n);
        }
        
    }
    return 0;
}

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