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
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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