Question

Check whether a number is Keith number.
A number is called Keith number if it appears in a special sequence (defined below) generated using its digits. The special sequence has first n terms as digits of number and other terms are recursively evaluated as sum of previous n terms

				
					ENTER A NUMBER:
197
197 is a keith number 

197 has 3 digits, so n = 3
The number is Keith because it appears in the special
sequence that has first three terms as 1, 9, 7 and 
remaining terms evaluated using sum of previous 3 terms.
1, 9, 7, 17, 33, 57, 107, 197, .....

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Code

				
					import java.util.Scanner;

public class keithNumber
{
    public static void main()
    {
        int digits[];
        int num=0,count=0,i=0,temp=0,sum=0;
        Scanner sc=new Scanner(System.in);
        System.out.println("ENTER THE NUMBER");   
        num=sc.nextInt();
        temp=num;
        while(temp>0)
        {
            count++;
            temp=temp/10;
        }
        digits=new int[count];
        System.out.println(count);
        temp=num;
        while(temp>0)
        {
            digits[count-1]=temp%10;
            temp/=10;
            count--;
        }
        
        while(sum< num)
        {
            sum=0;
            for(i=0;i< digits.length;i++)
            {
                sum=sum+digits[i];

            }
            for(i=0;i< digits.length-1;i++)
            {
                digits[i]=digits[i+1];
            }
            digits[digits.length-1]=sum;
            
        }
        
        if(sum==num)
        {
            System.out.println(num+" is keith number");   
        }
        else
        {
            System.out.println(num+" is not a keith number");
        }
    }
}