Hackerank: Interview Prep Kit: Repeating String.

Hi friends welcome to my channel, today we’ll be solving a problem from Hackerank, which you can locate under Interview Prep Kit, in the subcategory Warm-Up Challenges. Titled, Repeating String, quite easy, but tricky. So without much ado, let’s get to it. Note: I will be leaving the solutions in Javascript, Dart, and PHP.

Problem

There is a string, s, of lowercase English letters that is repeated infinitely many times. Given an integer, n, find and print the number of letter a's in the first n letters of the infinite string.

Example

s = 'abcac'
n = 10
The substring we consider is abcacabcac, the first 10 characters of the infinite string. There are  occurrences of a in the substring.

Function Description

Complete the repeatedString function in the editor below.
repeatedString has the following parameter(s):
s: a string to repeat
n: the number of characters to consider

Returns

int: the frequency of a in the substring

Input Format

The first line contains a single string, s.
The second line contains an integer, n.

Sample Input 0

aba
10

Sample Output 0

7

Explanation 0

The first n = 10 letters of the infinite string are abaabaabaa. Because there are 7 a's, we return 7

Sample Input 1

a
1000000000000

Sample Output 1

1000000000000

Explanation 1

Because all of the first n = 1000000000000 letters of the infinite string are a, we return 1000000000000

Solution in Dart.

Solution in Javascript

Solution in PHP

There you go, I’ll always encourage you to go through the problem and understand it, try to solve it yourself, then see my solutions and tell me what you think. You can reach me on LinkedIn and Twitter.