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 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)

Output:

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

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