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#include<stdio.h>
#include<math.h>
int main()
{

  int i,n,flag=0;
  scanf("%d",&n);
  for(i=2; i<=sqrt(n);i++)
  {
      if(n%i==0)
      {
          flag==1; //flag+=1
          break;
      }
  }

  if(flag==0)
  {
      printf("%d is prime number\n",n);
  }
  else
  {
      printf("%d is not prime number\n",n);
  }


  return 0;
}