Dado un número entero N , escriba un programa que devuelva verdadero si el número dado es un palíndromo, de lo contrario devuelva falso.
Ejemplos:
Input: N = 2002 Output: true Input: N = 1234 Output: false
Enfoque:
un método simple para este problema es invertir primero los dígitos de n y luego comparar el reverso de n con n . Si ambos son iguales, devuelve verdadero, de lo contrario, falso.
A continuación se muestra la implementación del enfoque anterior:
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
?>
Javascript
<script>
// Javascript program to check whether a number
// is Palindrome or not.
/* Iterative function to reverse digits of num*/
function reverseDigits(num)
{
let rev_num = 0;
while (num > 0) {
rev_num = rev_num * 10 + num % 10;
num = Math.floor(num / 10);
}
return rev_num;
}
/* Function to check if n is Palindrome*/
function isPalindrome(n)
{
// get the reverse of n
let 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*/
let n = 4562;
document.write("Is " + n + " a Palindrome number? -> ")
document.write(isPalindrome(n) == 1 ? "true" : "false" + "<br>");
n = 2002;
document.write("Is " + n + " a Palindrome number? -> ")
document.write(isPalindrome(n) == 1 ? "true" : "false");
// This code is contributed by Mayank Tyagi
</script>
Producción:
Is 4562 a Palindrome number? -> false Is 2002 a Palindrome number? -> true
Complejidad temporal: O(logN)
Espacio auxiliar: O(1)
Publicación traducida automáticamente
Artículo escrito por RishabhPrabhu y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA