Questions tagged [palindrome]
Any sequence of units (typically letters or numbers) that are read the same way forward or backward.
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Project Euler Problem #4 - Palindromic number
The problem is as follows:
A palindromic number reads the same both ways. The largest palindrome made from the product of two 2-digit numbers is 9009 = 91 × 99. Find the largest palindrome made ...
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Tests for palindromes in C and C++
A question I've been asked on interactive phone screens is to code a test to determine whether a string is
a palindrome or not. I am providing two examples here: one in C and one in C++. They both ...
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Improving time complexity of finding the longest palindrome in Python
The Longest Palindromic Substring challenge from InterviewBit:
Given a string S, find the longest palindromic substring in S.
where a "substring" must be contiguous, and in case of ties ...
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Check a string to see if it is a palindrome
I have written two code pieces to check if a given string is a palindrome:
...
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Count distinct primes, discarding palindromes, in under 2 seconds
Problem Statement
Generate as many distinct primes P such that reverse (P) is also prime
and is not equal to P.
Output:
Print per line one integer( ≤ 1015 ). Don't print more than
106 ...
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Palindromes in C
The function tests whether or not the provided string is a palindrome, and the main function just times how quick it is (after all, C's supposed to be quick, right?)...
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Longest palindrome in a string
Please be brutal, and judge my code as if it was written at a top 3 tech company, straight out of college. (The method signature, and input parameter is given by the problem, so don't worry about that)...
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Return the largest palindrome from the string
Here is the question: find the largest palindrome from a string.
Ex:
ABCBAHELLOHOWRACECARAREYOUILOVEUEVOLIIAMAIDOINGGOOD
Result:
...
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Test if a string is a palindrome
I got this out of an article on interviews / code challenges. The challenge text goes like this:
A palindrome is a word, phrase, number, or other sequence of
characters which reads the same ...
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answers
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Checking whether a string is a permutation of a palindrome in C++20
(See the next iteration/follow-up here.)
I have this short function is_permutation_palindrome, which returns true only if the ...
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Generalized Project Euler #4: Largest palindrome from product of two n-digit numbers in Python
This solves Project Euler 4: Largest palindrome product using Python (not limited to 3 digit numbers). I need suggestions for improvements to either the Python code or the math/algorithm since time of ...
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Checking whether a string is a permutation of a palindrome in C++20 - follow-up
This post is the follow-up of Checking whether a string is a permutation of a palindrome in C++20.
So, what's new? Well, nothing else except that the procedure is now generic and accepts all ...
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Finding the largest palindrome from the product of two n-digit numbers
The program finds the largest palindrome made from the product of two n-digit numbers, where n is specified by the user.
The code included works, however, when the user enters 5 or greater, the ...
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Determining if a sentence is a palindrome
The biggest problem I see in checking palindromes on the Internet is when the user inputs a palindrome sentence or phrase and the program returns a wrong output. So for me, I tried to optimize ...
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Leetcode 125. Valid Palindrome
Problem statement
Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases.
For example,
"A man, a plan, a canal: Panama" is a ...
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