#include<stdio.h>
int main()
{
  int num1=0;
  printf("Enter the number: ");
  scanf("%d",&num1);
  int largest = 1;
  if(num1 % 3 == 0)
  {
    largest = 3;
  }
  if(num1 % 5 == 0)
  {
    largest = 5;
  }
  if(num1 % 7 == 0)
  {
     largest = 7;
   
  }
  printf("The largest divisor among 1,3,5,7 is %d\n",largest);
  
  return 0;
}