**Question:**

Write a Program in Java to input a number and check whether it is a Bouncy Number or not.

**Increasing Number :** Working from left-to-right if no digit is exceeded by the digit to its left it is called an increasing number; for example, 22344.

**Decreasing Number :** Similarly if no digit is exceeded by the digit to its right it is called a decreasing number; for example, 774410.

**Bouncy Number :** We shall call a positive integer that is neither increasing nor decreasing a “bouncy” number; for example, 155349. Clearly there cannot be any bouncy numbers below 100.

**Solution:**

/** * The class BouncyNumber inputs a number and checks whether it is a Bouncy Number or not * @author : www.guideforschool.com * @Program Type : BlueJ Program - Java */ import java.util.*; class BouncyNumber { boolean isIncreasing(int n) //Function to check whether a number is Increasing { String s = Integer.toString(n); char ch; int f = 0; for(int i=0; i<s.length()-1; i++) { ch = s.charAt(i); if(ch>s.charAt(i+1))// If any digit is more than next digit then we have to stop checking { f = 1; break; } } if(f==1) return false; else return true; } boolean isDecreasing(int n) //Function to check whether a number is Decreasing { String s = Integer.toString(n); char ch; int f = 0; for(int i=0; i<s.length()-1; i++) { ch = s.charAt(i); if(ch<s.charAt(i+1))// If any digit is less than next digit then we have to stop checking { f = 1; break; } } if(f==1) return false; else return true; } void isBouncy(int n) { if(isIncreasing(n)==true) System.out.println("The number " + n + " is Increasing and Not Bouncy"); else if(isDecreasing(n)==true) System.out.println("The number " + n + " is Decreasing and Not Bouncy"); else System.out.println("The number " + n + " is bouncy"); } public static void main(String args[]) { Scanner sc = new Scanner(System.in); BouncyNumber ob = new BouncyNumber(); System.out.print("Enter a number : "); int n = sc.nextInt(); ob.isBouncy(n); } }

**Output:**

Enter a number : 22344

The number 22344 is Increasing and Not Bouncy

Enter a number : 774410

The number 774410 is Decreasing and Not Bouncy

Enter a number : 155349

The number 155349 is bouncy

155349

1<5

isIncreasing will return true…right?

No, as soon as it gets any digit more than earlier digit, it will return false. If all digits are less than next digit, then only it will return true.

Will I get full marks if i perform string operations on number programs like kaprekar number or keith number?

yes