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The Next Palindrome number

I am beginner in programming, So can you please tell me what’s wrong with my code?

I want to print next palindrome number if the number entered by the user (n) is not palindrome

n = int(input("Enter any number :- "))

reverse = 0
temp = n

while (n!=0):
    reverse = reverse * 10
    reverse = reverse + n%10
    n=n//10 
if(temp==reverse):
    print ("Already palindrome:: ")

if(temp != reverse):
     new_temp = temp
     new_reverse = 0
     for i in range(new_temp,new_temp+10):
        while(temp != 0):
            new_reverse = new_reverse * 10
            new_reverse = new_reverse + temp%10
            temp = temp//10
         if(new_temp==new_reverse):
             print ("Next pallindrome is :- ",new_temp)
             break
         if(new_temp != new_reverse):
             temp = new_temp+1

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Answer

There are two problems with your code.

1) Your “for i in range” loop calculates the reverse of the temp variable, but you don’t change the temp variable’s value. You do

 new_temp = temp
 for i in range(new_temp,new_temp+10):
    [SNIP]
    if(new_temp != new_reverse):
         temp = new_temp+1 #this value never changes.

So you’re making 10 iterations with one and the same value.

2) Ten iterations might not be enough to find a palindrome. Keep going until you find a palindrome.

Working code:

def reverse(num):
    reverse= 0
    while num:
        reverse= reverse*10 + num%10
        num= num//10
    return reverse

num= int(input("Enter any number :- "))
if num==reverse(num):
    print ("Already palindrome.")
else:
    while True:
        num+= 1
        if num==reverse(num):
            print ("Next palindrome is : %s"%num)
            break
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