Is Percentage of Letter in String easy or hard?

Percentage of Letter in String is considered an Easy problem. It focuses on basic string traversal, counting occurrences, and performing a simple percentage calculation.

Percentage of Letter in String Python/Java solution

In Python, you can use s.count(letter) to get the number of matches and return (count * 100) // len(s). In Java, iterate through the string using a loop, increment a counter when s.charAt(i) equals the target letter, then compute the integer percentage.

How to solve Percentage of Letter in String in O(n)?

Scan the string once and increment a counter whenever the current character equals the given letter. After finishing the iteration, compute the percentage using integer division: (count * 100) // len(s). Because each character is processed exactly once, the algorithm runs in O(n) time.

What is the best approach for Percentage of Letter in String?

The linear scan approach is the most common solution. Iterate through the string once, count how many characters match the given letter, then compute (count * 100) // n where n is the string length. This runs in O(n) time and O(1) space.

Is Percentage of Letter in String asked at Google/Amazon/Meta?

This problem is classified as an easy string traversal problem and appears frequently in coding practice platforms. While large companies typically ask harder variations, the underlying skills—string iteration and counting—are common building blocks in technical interviews.

What data structure is used in Percentage of Letter in String?

No complex data structure is required. The solution only uses the input string and a simple integer counter to track occurrences of the target character. The algorithm relies purely on sequential string traversal.

What is the time complexity of Percentage of Letter in String?

The time complexity is O(n), where n is the length of the string. Every character must be checked once to determine whether it matches the target letter. The space complexity remains O(1) since only a counter variable is stored.

Description Hints 2 Solution Video 2:52

2278. Percentage of Letter in String

Easy75.1% acceptance1 company

Given a string s and a character letter, return the percentage of characters in s that equal letter rounded down to the nearest whole percent.

Example 1:

Input: s = "foobar", letter = "o"
Output: 33
Explanation:
The percentage of characters in s that equal the letter 'o' is 2 / 6 * 100% = 33% when rounded down, so we return 33.

Example 2:

Input: s = "jjjj", letter = "k"
Output: 0
Explanation:
The percentage of characters in s that equal the letter 'k' is 0%, so we return 0.

Constraints:

1 <= s.length <= 100
s consists of lowercase English letters.
letter is a lowercase English letter.

Asked at 1 company

American Express

Topics

String

Hints open one at a time

Hint 1

Can we count the number of occurrences of letter in s?

Hint 2

Recall that the percentage is calculated as (occurrences / total) * 100.

2:52

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