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Suresh Ayyanna
Suresh Ayyanna

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Reverse a Number (Java)

Program to find Reverse of a Number

package InterviewPrograms;

import java.util.Scanner;

public class ReverseNumber {
    static int revNum = 0;

    // Method 01:Using Algorithm
    public static int reverseOfNumber(int num) {
        while (num != 0) {
            revNum = revNum * 10 + num % 10;
            num = num / 10;
        }
        return revNum;
    }

    // Method 02: using StringBuffer class
    public static StringBuffer reversedNumber(int number) {

        StringBuffer sb = new StringBuffer(String.valueOf(number));
        StringBuffer rev = sb.reverse();
        return rev;
    }

    // Method 03: using StringBuilder class
    public static StringBuilder reversedNum(int value) {

        StringBuilder sb1 = new StringBuilder();
        StringBuilder revValue = sb1.append(value).reverse();
        return revValue;
    }

    public static void main(String[] args) {
        System.out.println("Enter the number: ");
        Scanner input = new Scanner(System.in);
        int actualNumber = input.nextInt();

        System.out.println("Reverse of a number using Method 01: " + reverseOfNumber(actualNumber));
        System.out.println("Reverse of a number using Method 02: " + reversedNumber(actualNumber));
        System.out.println("Reverse of a number using Method 03: " + reversedNum(actualNumber));

    }
}

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