Lucky_22.java

// Java program to check Lucky Number 
import java.util.*; 
class Lucky_22 
{ 
	public static int counter = 2;	 

	// Returns 1 if n is a lucky no. ohterwise returns 0 
	static boolean isLucky(int n) 
	{ 
		// variable next_position is just for readability of 
		// the program we can remove it and use n only 
		int next_position = n; 
		if(counter > n) 
			return true; 
		if(n%counter == 0) 
			return false;	 

		// calculate next position of input no 
		next_position -= next_position/counter; 
	
		counter++; 
		return isLucky(next_position); 
	} 
	
	// driver program 
	public static void main (String[] args) 
	{ 
		int x = 5; 
		if( isLucky(x) ) 
			System.out.println(x+" is a lucky no."); 
		else
			System.out.println(x+" is not a lucky no."); 
	} 
}