How should I practice Palindrome Match Percentage?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Apple onsite interview problems in FastPrep.

Is Palindrome Match Percentage associated with Apple?

FastPrep tags this as a Apple onsite interview coding practice problem when the problem catalog has that company and stage context.

Problem · String

Palindrome Match Percentage

Learn this problem

● Easy

AppleFULLTIMEONSITE INTERVIEW

Problem statement

Given a string text, measure how closely it matches a palindrome by comparing mirrored character pairs.

Let pairs = floor(text.length / 2). Count a pair when text[i] == text[text.length - 1 - i] for 0 <= i < pairs. The middle character of an odd-length string does not form a pair.

Return 100 × matchingPairs / pairs as a string with exactly two digits after the decimal point, rounded to the nearest hundredth with half values rounded up. Strings of length zero or one return "100.00".

Comparison is case-sensitive and literal: spaces and punctuation are not removed.

Function

palindromeMatchPercentage(text: String) → String

Examples

Example 1

text = "racecar"return = "100.00"

All three mirrored pairs match. The middle e is excluded.

Example 2

text = "abca"return = "50.00"

The outer a pair matches, while b and c do not.

Example 3

text = "abcdefa"return = "33.33"

One of the three mirrored pairs matches, so the exact fraction is rounded to 33.33.

Constraints

0 <= text.length <= 20000.
text contains printable ASCII characters, including spaces and punctuation.
The returned value always contains exactly two digits after the decimal point.