Program to print weather the number is happy or not.

#include<stdio.h>
#include<math.h>
int main()
{
 int i,j,num,temp,sum=0;
 printf("Enter number\n");
 scanf("%d",&num);
  while(sum!=1 && sum!=4)
  {
   sum=0;
   while(num>0)
  {
    j=num%10;
    sum+=(j*j);
    num=num/10;
  }
  num=sum;
  }

 if(sum==1)
 printf("Happy Number\n");
 else
 printf("UnHappy Number\n");
}