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
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 Programint main(){ ReverseandAdd(195); ReverseandAdd(265); return 0;} |
Java
// Java Program to implement reverse and add functionpublic 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 numdef 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 notdef isPalindrome(num): return (reversDigits(num) == num) # Reverse and Add Functiondef 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 CodeReverseandAdd(195)ReverseandAdd(265) |
C#
// C# Program to implement reverse and add functionusing 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 CodeReverseandAdd(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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