Program to check the number is Palindrome or not

Given an integer N, write a program that returns true if the given number is a palindrome, else return false.

Examples:

Input: N = 2002 
Output: true

Input: N = 1234
Output: false

Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

Approach:
A simple method for this problem is to first reverse digits of n, then compare the reverse of n with n. If both are same, then return true, else false.

Below is the implementation of the above approach:

C++

// C program to check whether a number 
// is Palindrome or not. 
  
#include <stdio.h> 
  
/* Iterative function to reverse digits of num*/
int reverseDigits(int num) 
{ 
    int rev_num = 0; 
    while (num > 0) { 
        rev_num = rev_num * 10 + num % 10; 
        num = num / 10; 
    } 
    return rev_num; 
} 
  
/* Function to check if n is Palindrome*/
int isPalindrome(int n) 
{ 
  
    // get the reverse of n 
    int rev_n = reverseDigits(n); 
  
    // Check if rev_n and n are same or not. 
    if (rev_n == n) 
        return 1; 
    else
        return 0; 
} 
  
/*Driver program to test reversDigits*/
int main() 
{ 
    int n = 4562; 
    printf("Is %d a Palindrome number? -> %s\n", n, 
           isPalindrome(n) == 1 ? "true" : "false"); 
  
    n = 2002; 
    printf("Is %d a Palindrome number? -> %s\n", n, 
           isPalindrome(n) == 1 ? "true" : "false"); 
    return 0; 
} 

Java

// Java program to check whether a number 
// is Palindrome or not. 
  
class GFG 
{ 
    /* Iterative function to reverse digits of num*/
    static int reverseDigits(int num) 
    { 
        int rev_num = 0; 
        while (num > 0) { 
            rev_num = rev_num * 10 + num % 10; 
            num = num / 10; 
        } 
        return rev_num; 
    } 
      
    /* Function to check if n is Palindrome*/
    static int isPalindrome(int n) 
    { 
      
        // get the reverse of n 
        int rev_n = reverseDigits(n); 
      
        // Check if rev_n and n are same or not. 
        if (rev_n == n) 
            return 1; 
        else
            return 0; 
    } 
      
    /*Driver program to test reversDigits*/
    public static void  main(String []args) 
    { 
        int n = 4562; 
        System.out.println("Is" + n + "a Palindrome number? -> " + 
            (isPalindrome(n) == 1 ? "true" : "false")); 
      
        n = 2002; 
          
        System.out.println("Is" + n + "a Palindrome number? -> " + 
            (isPalindrome(n) == 1 ? "true" : "false")); 
  
    } 
  
} 
  
// This code is contributed  
// by Hritik Raj ( ihritik ) 

Python3

# Python3 program to check whether a  
# number is Palindrome or not.  
  
# Iterative function to reverse 
# digits of num 
def reverseDigits(num) :  
  
    rev_num = 0;  
    while (num > 0) : 
        rev_num = rev_num * 10 + num % 10
        num = num // 10
      
    return rev_num  
  
# Function to check if n is Palindrome 
def isPalindrome(n) : 
  
    # get the reverse of n  
    rev_n = reverseDigits(n);  
  
    # Check if rev_n and n are same or not.  
    if (rev_n == n) : 
        return 1
    else : 
        return 0
  
# Driver Code 
if __name__ == "__main__" : 
  
    n = 4562
      
    if isPalindrome(n) == 1 : 
        print("Is", n, "a Palindrome number? ->", True) 
          
    else : 
        print("Is", n, "a Palindrome number? ->", False) 
  
    n = 2002
      
    if isPalindrome(n) == 1 : 
        print("Is", n, "a Palindrome number? ->", True) 
          
    else : 
        print("Is", n, "a Palindrome number? ->", False) 
  
# This code is contributed by Ryuga 

C#

// C# program to check whether a number 
// is Palindrome or not. 
  
using System; 
class GFG 
{ 
    /* Iterative function to reverse digits of num*/
    static int reverseDigits(int num) 
    { 
        int rev_num = 0; 
        while (num > 0) { 
            rev_num = rev_num * 10 + num % 10; 
            num = num / 10; 
        } 
        return rev_num; 
    } 
      
    /* Function to check if n is Palindrome*/
    static int isPalindrome(int n) 
    { 
      
        // get the reverse of n 
        int rev_n = reverseDigits(n); 
      
        // Check if rev_n and n are same or not. 
        if (rev_n == n) 
            return 1; 
        else
            return 0; 
    } 
      
    /*Driver program to test reversDigits*/
    public static void  Main() 
    { 
        int n = 4562; 
        Console.WriteLine("Is" + n + "a Palindrome number? -> " + 
            (isPalindrome(n) == 1 ? "true" : "false")); 
      
        n = 2002; 
          
        Console.WriteLine("Is" + n + "a Palindrome number? -> " + 
            (isPalindrome(n) == 1 ? "true" : "false")); 
  
    } 
  
} 
  
// This code is contributed  
// by Hritik Raj ( ihritik ) 

PHP

<?php 
// PHP program to check whether a number 
// is Palindrome or not. 
  
// Iterative function to reverse  
// digits of num 
function reverseDigits($num) 
{ 
    $rev_num = 0; 
    while ($num > 0)  
    { 
        $rev_num = $rev_num * 10 +  
                   $num % 10; 
        $num = $num / 10; 
    } 
    return $rev_num; 
} 
  
// Function to check if n is Palindrome 
function isPalindrome($n) 
{ 
  
    // get the reverse of n 
    $rev_n = reverseDigits($n); 
  
    // Check if rev_n and n are same or not. 
    if ($rev_n == $n) 
        return 1; 
    else
        return 0; 
} 
  
// Driver Code 
$n = 4562; 
echo "Is ", $n , " a Palindrome number? ->"; 
  
if(isPalindrome($n) == 1) 
    echo "true" ; 
else
    echo "false"; 
echo "\n"; 
  
$n = 2002; 
echo "Is ", $n , " a Palindrome number? ->"; 
if(isPalindrome(!$n)) 
    echo "true" ; 
else
    echo "false"; 
  
// This code is contributed by jit_t 
?> 

Output:

Is 4562 a Palindrome number? -> false
Is 2002 a Palindrome number? -> true

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My Personal Notes

Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

C++

Java

Python3

C#

PHP

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