Palindrome Program in Python 1

Palindrome Program in Python

Write a Palindrome Number Program in Python using While Loop, Functions, and Recursion. Any number could be Palindrome if it remained the same when we reversed it. For example, 131 because it remains the same after reversing it.

The common approach to check for the Palindrome Number is to reverse a given number. Compare the original value with the reverse value. If they exactly matched, then it is a Palindrome number. Otherwise, it is not.

Python Palindrome Number Program using While Loop

This program allows the user to enter any integer value. Next, this program uses While Loop to check whether a given number is Palindrome or Not.

# using While Loop
number = int(input("Please Enter any Value: "))

reverse = 0
temp = number

while(temp > 0):
    Reminder = temp % 10
    reverse = (reverse * 10) + Reminder
    temp = temp //10
 
print("Reverse of it is = %d" %reverse)

if(number == reverse):
    print("%d is a Palindrome" %number)
else:
    print("%d is Not" %number)
Palindrome Program in Python 1

User Entered value in this palindrome program in Python are Number = 191 and Reverse = 0
Temp = Number
Temp = 191

While Loop First Iteration
Reminder = Temp %10
Reminder = 191 % 10 = 1

Reverse = Reverse *10 + Reminder => 0 * 10 + 1 = 1

Temp = Temp //10 = 191 /10
Temp = 19

Second Iteration: From the first while loop Iteration, the values changed as Temp = 19 and Reverse = 1

Reminder = 19 % 10 = 9

Reverse = 1 * 10 + 9 = 19

Temp = 19 /10
Temp = 1

Third Iteration: From the Second Iteration, the values of Temp = 1 and Reverse = 19

Reminder = 1 % 10 = 1

Reverse = 19 * 10 + 1 = 191

Temp = 1/10
Temp = 0

Here Num = 0. So, the Python while loop condition fails.

if ( Number == Reverse ) – condition checks whether the user entered number is exactly equal to the Reverse or not. If this condition is True, then it is. Else it is not.

Python Palindrome Number Program using Functions

In this program, we defined a function. Within that function, we used the If statement.

# using Functions
def intRev(val):
    inverse = 0
    
    while(val > 0):
        Remi = val % 10
        inverse = (inverse * 10) + Remi
        val = val // 10
    return inverse

val = int(input("Please Enter any Num: "))

rev = intRev(val)
print("Inverse = %d" %rev)

if(val == rev):
    print("%d is a Palindrome" %val)
else:
    print("%d is not" %val)
Please Enter any Num: 1441
Inverse = 1441
1441 is a Palindrome

Please Enter any Num: 1202
Inverse = 2021
1202 is not

Using recursion

In this Python program, we are checking whether a given number is Palindrome or Not using the Recursive Functions concept.

# using Recursive Functions
rev = 0
def integer_rev(num):
    global rev
    
    if(num > 0):
        Reminder = num % 10
        rev = (rev * 10) + Reminder
        integer_rev(num // 10)
    return rev


num = int(input("Please Enter any Num: "))

rev = integer_rev(num)
print("Reverse = %d" %rev)

if(num == rev):
    print("%d is a Palindrome" %num)
else:
    print("%d is not" %num)
Please Enter any Num: 4114
Reverse = 4114
4114 is a Palindrome

=================== RESTART: ===================
Please Enter any Num: 859
Reverse = 958
859 is not

In this program, within the checks using recursion function declaration,

integer_rev (Num//10) – it helps to call the function Recursively with the updated value. If you miss this statement, it terminates after completing the first line. For example, Num = 191, then the output is 1

Let’s see the If condition.

if (num > 0) check whether it is greater than 0 or not. For Recursive functions, placing a condition before using the function recursively is very important. Otherwise, we end up in infinite execution (Same as infinite Loop).

Python program to print Palindrome Numbers from 1 to N

maximum = int(input(" Please Enter the Maximum Value : "))

print("Between 1 and %d are : " %maximum)
for num in range(1, maximum + 1):
    temp = num
    rv = 0
    
    while(temp > 0):
        Reminder = temp % 10
        rv = (rv * 10) + Reminder
        temp = temp //10

    if(num == rv):
        print("%d " %num, end = '  ')
 Please Enter the Maximum Value : 4554
Between 1 and 4554 are : 
1   2   3   4   5   6   7   8   9   11   22   33   44   55   66   77   88   99   101   111   121   131   141   151   161   171   181   191   202   212   222   232   242   252   262   272   282   292   303   313   323   333   343   353   363   373   383   393   404   414   424   434   444   454   464   474   484   494   505   515   525   535   545   555   565   575   585   595   606   616   626   636   646   656   666   676   686   696   707   717   727   737   747   757   767   777   787   797   808   818   828   838   848   858   868   878   888   898   909   919   929   939   949   959   969   979   989   999   1001   1111   1221   1331   1441   1551   1661   1771   1881   1991   2002   2112   2222   2332   2442   2552   2662   2772   2882   2992   3003   3113   3223   3333   3443   3553   3663   3773   3883   3993   4004   4114   4224   4334   4444   4554