Check if number is palindrome or not in Octal

Last Updated : 5 Sep, 2022

Given a number which may be in octal or in decimal. If the number is not octal then convert it into octal then check if it is palindrome or not. If it is palindrome then print 1 otherwise print 0. If the number is already in octal then check if the number is palindrome or not.
Examples : 
 

Input :n = 111
Output : Yes
Explanation:
all digits of 111 are in 0-7 so it 
is a octal number. Read 111 the result
is same backward and forward so it 
is a palindrome number. 

Input : 68
Output : No
Explanation:
68 is not a octal number because it's 
all digits are not in 0-7. So first we 
need to convert it into octal 
(68)base10(Decimal) = (104)base8(octal) 
104 is not palindrome.
 
Input : 97
Output : Yes
Explanation:
97 is not a octal number because it's all
digits are not in 0-7 so first we need to 
convert it into decimal to octal 
(97)base10(Decimal) = (141)base8(octal)  
141 is palindrome so output = 1.


 


Octal Number : The octal numeral system, or oct for short, is the base-8 number system, and uses the digits 0 to 7.
How to Convert Decimal Number to Octal Number : 
 

https://media.geeksforgeeks.org/wp-content/uploads/Capture-21.png


 

C++ 
// C++ program to check if octal
// representation of a number is prime
#include <iostream>
using namespace std;

const int MAX_DIGITS = 20;

/* Function to Check no is in octal
or not */
bool isOctal(long n)
{
    while (n)
    {
        if ((n % 10) >= 8)
            return false;
        else
            n = n / 10;
    }
    return true;
}

/* Function To check no is palindrome
or not*/
int isPalindrome(long n)
{
    // If number is already in octal, we traverse
    // digits using repeated division with 10. Else
    // we traverse digits using repeated division 
    // with 8
    int divide = (isOctal(n) == false)? 8 : 10;

    // To store individual digits 
    int octal[MAX_DIGITS];

    // Traversing all digits
    int i = 0;
    while (n != 0)
    {
        octal[i++] = n % divide;
        n = n / divide;
    }

    // checking if octal no is palindrome
    for (int j = i - 1, k = 0; k <= j; j--, k++)
        if (octal[j] != octal[k])
            return false;

    return true;
}

// Driver code
int main()
{
    long n = 97;
    if (isPalindrome(n))
    cout << "Yes";
    else
    cout << "No";
    return 0;
}
Java 
// Java program to check if 
// octal representation of 
// a number is prime
import java.io.*;
import java.util.*;
import java.lang.*;

class GFG
{
static int MAX_DIGITS = 20;

/* Function to Check no 
is in octal or not */
static int isOctal(int n)
{
    while (n > 0)
    {
        if ((n % 10) >= 8)
            return 0;
        else
            n = n / 10;
    }
    return 1;
}

/* Function To check no 
is palindrome or not*/
static int isPalindrome(int n)
{
    // If number is already in 
    // octal, we traverse digits
    // using repeated division 
    // with 10. Else we traverse 
    // digits using repeated 
    // division with 8
    int divide = (isOctal(n) == 0) ? 8 : 10;

    // To store individual digits 
    int octal[] = new int[MAX_DIGITS];

    // Traversing all digits
    int i = 0;
    while (n != 0)
    {
        octal[i++] = n % divide;
        n = n / divide;
    }

    // checking if octal 
    // no is palindrome
    for (int j = i - 1, 
            k = 0; k <= j; j--, k++)
        if (octal[j] != octal[k])
            return 0;

    return 1;
}

// Driver Code
public static void main(String[] args)
{
    int n = 97;
    if (isPalindrome(n) > 0)
    System.out.print("Yes");
    else
    System.out.print("No");
}
}

// This code is contributed 
// by Akanksha Rai(Abby_akku)
Python3 
# Python3 program to check if 
# octal representation of 
# a number is prime
MAX_DIGITS = 20;

# Function to Check no 
# is in octal or not
def isOctal(n):
    while(n):
        if((n % 10) >= 8):
            return False
        else:
            n = int(n / 10)
    return True

# Function To check no 
# is palindrome or not
def isPalindrome(n):
    # If number is already in 
    # octal, we traverse digits 
    # using repeated division 
    # with 10. Else we traverse 
    # digits using repeated 
    # division with 8
    divide = 8 if(isOctal(n) == False) else 10

    # To store individual digits 
    octal=[]

    # Traversing all digits
    while (n != 0):
        octal.append(n % divide)
        n = int(n / divide)

    # checking if octal 
    # no is palindrome
    j = len(octal)-1
    k = 0
    while(k <= j):
        if(octal[j] != octal[k]):
            return False
        j-=1
        k+=1
    return True


# Driver Code
if __name__=='__main__':
    n = 97;
    if (isPalindrome(n)):
        print("Yes")
    else:
        print("No")

# This code is contributed by mits
C# 
// C# program to check if 
// octal representation of 
// a number is prime
using System;

class GFG
{
static long MAX_DIGITS = 20;

/* Function to Check no 
is in octal or not */
static long isOctal(long n)
{
    while (n > 0)
    {
        if ((n % 10) >= 8)
            return 0;
        else
            n = n / 10;
    }
    return 1;
}

/* Function To check no 
is palindrome or not*/
static long isPalindrome(long n)
{
    // If number is already in 
    // octal, we traverse digits
    // using repeated division 
    // with 10. Else we traverse 
    // digits using repeated 
    // division with 8
    long divide = (isOctal(n) == 0) ? 8 : 10;

    // To store individual digits 
    long[] octal = new long[MAX_DIGITS];

    // Traversing all digits
    long i = 0;
    while (n != 0)
    {
        octal[i++] = n % divide;
        n = n / divide;
    }

    // checking if octal 
    // no is palindrome
    for (long j = i - 1, 
            k = 0; k <= j; j--, k++)
        if (octal[j] != octal[k])
            return 0;

    return 1;
}

// Driver Code
static int Main()
{
    long n = 97;
    if (isPalindrome(n) > 0)
    Console.Write("Yes");
    else
    Console.Write("No");
    return 0;
}
}

// This code is contributed 
// by mits
PHP 
<?php
// PHP program to check if 
// octal representation of 
// a number is prime
$MAX_DIGITS = 20;

// Function to Check no 
// is in octal or not
function isOctal($n)
{
    while ($n)
    {
        if (($n % 10) >= 8)
            return false;
        else
            $n = (int)$n / 10;
    }
    return true;
}

// Function To check no 
// is palindrome or not
function isPalindrome($n)
{
    global $MAX_DIGITS;
    // If number is already in 
    // octal, we traverse digits 
    // using repeated division 
    // with 10. Else we traverse 
    // digits using repeated 
    // division with 8
    $divide = (isOctal($n) ==
                false) ? 8 : 10;

    // To store individual digits 
    $octal;

    // Traversing all digits
    $i = 0;
    while ($n != 0)
    {
        $octal[$i++] = $n % $divide;
        $n = (int)$n / $divide;
    }

    // checking if octal 
    // no is palindrome
    for ($j = $i - 1, $k = 0;
        $k <= $j; $j--, $k++)
        if ($octal[$j] != $octal[$k])
            return -1;

    return 0;
}

// Driver Code
$n = 97;
if (isPalindrome($n))
echo "Yes";
else
echo "No";

// This code is contributed by ajit
?>
JavaScript 
<script>

// Javascript program to check if octal 
// representation of a number is prime 

const MAX_DIGITS = 20; 

/* Function to Check no is in octal 
or not */
function isOctal(n) 
{ 
    while (n) 
    { 
        if ((n % 10) >= 8) 
            return false; 
        else
            n = Math.floor(n / 10); 
    } 
    return true; 
} 

/* Function To check no is palindrome 
or not*/
function isPalindrome(n) 
{ 
    // If number is already in octal, we traverse 
    // digits using repeated division with 10. Else 
    // we traverse digits using repeated division 
    // with 8 
    var divide = (isOctal(n) == false)? 8 : 10; 

    // To store individual digits 
    var octal = new Array(MAX_DIGITS); 

    // Traversing all digits 
    var i = 0; 
    while (n != 0) 
    { 
        octal[i++] = n % divide; 
        n = Math.floor(n / divide); 
    } 

    // checking if octal no is palindrome 
    for (var j = i - 1, k = 0; k <= j; j--, k++) 
        if (octal[j] != octal[k]) 
            return false; 

    return true; 
} 

// Driver code 

    var n = 97; 
    if (isPalindrome(n)) 
    document.write("Yes"); 
    else
    document.write("No"); 

// This code is contributed by Mayank Tyagi

</script>

Output : 
 

Yes

Time complexity: O(logn) where n is given input number

Auxiliary Space: O(1)
 

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Article Tags:
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Mathematical
DSA
palindrome

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