Reverse and Add Function

The reverse and add function starts with a number, reverses its digits, and adds the reverse to the original. If the sum is not a palindrome, repeat this procedure until it does.

Write a program that takes number and gives the resulting palindrome (if one exists). If it took more than 1,000 iterations (additions) or yield a palindrome that is greater than 4,294,967,295, assume that no palindrome exist for the given number.

Examples:

Input : 195
Output : 9339

Input : 265
Output: 45254

Input : 196
Output : No palindrome exist

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

C++

// C++ Program to implement reverse and add function 
#include<bits/stdc++.h> 
using namespace std; 
  
/* Iterative function to reverse digits of num*/
long long reversDigits(long long num) 
{ 
    long long rev_num = 0; 
    while (num > 0) 
    { 
        rev_num = rev_num*10 + num%10; 
        num = num/10; 
    } 
    return rev_num; 
} 
  
/* Function to check whether he number is palindrome or not */
bool isPalindrome(long long num) 
{ 
    return (reversDigits(num) == num); 
} 
  
/* Reverse and Add Function */
void ReverseandAdd(long long num) 
{ 
    long long rev_num=0; 
    while (num <= 4294967295) 
    { 
        // Reversing the digits of the number 
        rev_num = reversDigits(num); 
  
        // Adding the reversed number with the original 
        num = num + rev_num; 
  
        // Checking whether the number is palindrome or not 
        if (isPalindrome(num)) 
        { 
            printf("%lld\n",num); 
            break; 
        } 
        else if (num > 4294967295) 
        { 
            printf("No palindrome exist"); 
        } 
    } 
} 
  
// Driver Program 
int main() 
{ 
    ReverseandAdd(195); 
    ReverseandAdd(265); 
    return 0; 
} 

Java

// Java Program to implement reverse and add function 
public class ReverseAdd  
{ 
    /* Iterative function to reverse digits of num*/
    long reversDigits(long num) 
    { 
        long rev_num = 0; 
        while (num > 0) 
        { 
            rev_num = rev_num*10 + num%10; 
            num = num/10; 
        } 
        return rev_num; 
    } 
  
    /* Function to check whether he number is 
           palindrome or not */
    boolean isPalindrome(long num) 
    { 
        return (reversDigits(num) == num); 
    } 
  
    /* Reverse and Add Function */
    void ReverseandAdd(long num) 
    { 
        long rev_num = 0; 
        while (num <= 4294967295l) 
        { 
            // Reversing the digits of the number 
            rev_num = reversDigits(num); 
  
            // Adding the reversed number with the original 
            num = num + rev_num; 
  
            // Checking whether the number is palindrome or not 
            if(isPalindrome(num)) 
            { 
                System.out.println(num); 
                break; 
            } 
            else if (num > 4294967295l) 
            { 
                System.out.println("No palindrome exist"); 
            } 
        } 
    } 
      
    // Main method 
    public static void main(String[] args)  
    { 
        ReverseAdd ob = new ReverseAdd(); 
        ob.ReverseandAdd(195l); 
        ob.ReverseandAdd(265l); 
          
    } 
} 

Python

#Python Program to implement reverse and add function 
  
# Iterative function to reverse digits of num 
def reversDigits(num): 
    rev_num=0
    while (num > 0): 
        rev_num = rev_num*10 + num%10
        num = num/10
    return rev_num 
  
# Function to check whether the number is palindrome or not 
def isPalindrome(num): 
    return (reversDigits(num) == num) 
  
# Reverse and Add Function 
def ReverseandAdd(num): 
    rev_num = 0
    while (num <= 4294967295): 
        # Reversing the digits of the number 
        rev_num = reversDigits(num) 
  
        # Adding the reversed number with the original 
        num = num + rev_num 
  
        # Checking whether the number is palindrome or not 
        if(isPalindrome(num)): 
            print num 
            break
        else: 
            if (num > 4294967295): 
                print "No palindrome exist"
  
# Driver Code 
ReverseandAdd(195) 
ReverseandAdd(265) 

C#

// C# Program to implement reverse and add function 
using System; 
  
class GFG  
{ 
    /* Iterative function to reverse digits of num*/
    static long reversDigits(long num) 
    { 
        long rev_num = 0; 
        while (num > 0) 
        { 
            rev_num = rev_num * 10 + num % 10; 
            num = num / 10; 
        } 
        return rev_num; 
    } 
  
    /* Function to check whether he number is 
        palindrome or not */
    static bool isPalindrome(long num) 
    { 
        return (reversDigits(num) == num); 
    } 
  
    /* Reverse and Add Function */
    static void ReverseandAdd(long num) 
    { 
        long rev_num = 0; 
        while (num <= 4294967295) 
        { 
            // Reversing the digits of the number 
            rev_num = reversDigits(num); 
  
            // Adding the reversed number with the original 
            num = num + rev_num; 
  
            // Checking whether the number is palindrome or not 
            if(isPalindrome(num)) 
            { 
                Console.WriteLine(num); 
                break; 
            } 
            else if (num > 4294967295) 
            { 
                Console.WriteLine("No palindrome exist"); 
            } 
        } 
    } 
      
    // Driver code 
    public static void Main()  
    { 
        ReverseandAdd(195); 
        ReverseandAdd(265); 
    } 
} 
  
// This code is contributed by chandan_jnu 

PHP

<?php 
// PHP Program to implement reverse and add function 
  
/* Iterative function to reverse digits of num*/
function reversDigits($num) 
{ 
    $rev_num = 0; 
    while ($num > 0) 
    { 
        $rev_num = $rev_num * 10 + $num % 10; 
        $num = (int)($num / 10); 
    } 
    return $rev_num; 
} 
  
/* Function to check whether he number 
   is palindrome or not */
function isPalindrome($num) 
{ 
    return (reversDigits($num) == $num); 
} 
  
/* Reverse and Add Function */
function ReverseandAdd($num) 
{ 
    $rev_num = 0; 
    while ($num <= 4294967295) 
    { 
        // Reversing the digits of the number 
        $rev_num = reversDigits($num); 
  
        // Adding the reversed number with 
        // the original 
        $num = $num + $rev_num; 
  
        // Checking whether the number is 
        // palindrome or not 
        if (isPalindrome($num)) 
        { 
            print($num . "\n"); 
            break; 
        } 
        else if ($num > 4294967295) 
        { 
            print("No palindrome exist"); 
        } 
    } 
} 
  
// Driver Code 
ReverseandAdd(195); 
ReverseandAdd(265); 
  
// This code is contributed by chandan_jnu 
?> 

Output:

9339
45254

References: https://app.assembla.com/spaces/AASU_Fall2008_ProgrammingTeam/wiki

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