#include<stdio.h>
#include<math.h>
int main()
{
long n,b,i,bin,c,d,num,rev,bin2;
while(scanf("%ld",&n)==1)
{
num=n;
bin=0;
rev=0;
bin2=0;
if(n==2)
{
printf("%ld is prime.\n",n);
continue;
}
b=(int)sqrt(n);
if(n%2==0)
{
bin=1;
printf("%ld is not prime.\n",n);
}
else
for (i=3;i<=b;i+=2)
if (n%i==0)
{
printf("%ld is not prime.\n",n);
bin=1; break;
}
if(bin==0)
{
for(i=1;i!=0;i++)
{
d=num%10;
num=num/10;
rev=rev*10+d;
if(num==0)
break;
}
if(rev==n)
{
printf("%ld is prime.\n",n);
continue;
}
c=(int)sqrt(rev);
if(rev%2==0)
{
bin2=1;
printf("%ld is prime.\n",n);
}
else
for (i=3;i<=c;i+=2)
if (rev%i==0)
{
printf("%ld is prime.\n",n);
bin2=1; break;
}
if(bin2==0)
printf("%ld is emirp.\n",n);
}
}
return 0;
}
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