- Write a C++ program to check whether a number is palindrome or not.

Before jumping to a C++ program to check whether a number is palindrome or not, here is a brief overview of palindrome numbers.

**A number is palindrome, if number remains same after reversing it's digits.**

1234321 is palindrome number, but 123456 is not a palindrome number.

To check whether N is palindrome number or not, first of all we have to reverse the sequence of digits of N and then compare it with original N. If both are equal then N is palindrome number.

**Algorithm to check a number is palindrome or not**

- Take a number as input from user and store it in an integer variable(Let's call it inputNumber).
- Reverse the digits of inputNumber, and store it in another integer variable(Let's call it reverseNumber).
- Compare inputNumber and reverseNumber.
- If both are equal then inputNumber is palindrome number otherwise not a palindrome number.

## C++ program to check palindrome number

#include <iostream> using namespace std; int main(){ int inputNumber, reverseNumber = 0, rightDigit, temp; cout << "Enter a number\n"; cin >> inputNumber; temp = inputNumber; // reverse inputNumber and store it in reverseNumber while(temp != 0){ rightDigit = temp % 10; reverseNumber = (reverseNumber * 10) + rightDigit; temp = temp/10; } // If input Number and reverse Number are same // then palindrome othrwise not if(reverseNumber == inputNumber){ cout << inputNumber << " is Palindrome Number"; } else { cout << inputNumber << " is not a Palindrome Number"; } return 0; }Output

Enter a number 1234321 1234321 is Palindrome Number

Enter a number 123456 123456 is not a Palindrome Number

In above program, we first take a number as input from user using cin and store it in variable original. Copy the value of original variable to another variable copy. Then using a while loop, we reverse the sequence of digits of a number. Finally, we compare reverse and original number. If both are equal then input number is palindrome otherwise not a palindrome number.

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