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![def repeatedString(s, n):
'''Computes and returns total number of occurrences of the character 'a'
in the prefix of length n of an infinitely repeating string.
Parameters:
s - Input string which is considered to be repeated infinitely.
n - The first number of letters to be considered for counting number
of occurrences of the character 'a' in the infinite string.
Returns:
Total number of occurrences of the character 'a'.
'''
# Length of string.
len_str = len(s)
# Number of repeated strings to be considered.
num_strs = n//len_str
# Remainder: Let's consider an example - s = 'abc' and n = 11.
# Therefore, the string to be considered for finding the number
# of occurrences of 'a' will be: 'abcabcabcab'. The string is
# repeating 3 times(abcabcabc). Now, remaining letters are only 2(ab).
# Therefore, length of remaining letters is calculated as below syntax.
remainder = n%len_str
# Counter to count number of a's from given string.
count1 = 0
# Counter to count a's from the remaining set of letters. In the end, it
# will be used to calculate total number of a's in the string.
count2 = 0
for i in range(len_str):
# Calculating number of occurrences of character 'a' from the given string
if s[i] == 'a':
count1 += 1
# Calculating number of occurrences from remaining letters
# if they exist.
if s[i] == 'a' and i < remainder:
count2 += 1
# Calculating total number of a's in the string
total = count1*num_strs + count2
return total
# Testing
print(repeatedString('aba', 10))](https://image.slidesharecdn.com/repeated-string-english-merged-190211223226/85/HackerRank-Repeated-String-Problem-2-320.jpg)
HackerRank Repeated String Problem
- 1. Repeated String Lilah has a string, , of lowercase English letters that she repeated infinitely many times. Given an integer, , find and print the number of letter a 's in the first letters of Lilah's infinite string. Input Format The first line contains a single string, . The second line contains an integer, . Constraints For of the test cases, . Output Format Print a single integer denoting the number of letter a 's in the first letters of the infinite string created by repeating infinitely many times. Sample Input 0 aba 10 Sample Output 0 7 Explanation 0 The first letters of the infinite string are abaabaabaa . Because there are a 's, we print on a new line. Sample Input 1 a 1000000000000 Sample Output 1 1000000000000 Explanation 1 Because all of the first letters of the infinite string are a , we print on a new line.
- 2. def repeatedString(s, n): '''Computesand returns total number of occurrences of the character 'a' in the prefix of length n of an infinitely repeating string. Parameters: s - Input string which is considered to be repeated infinitely. n - The first number of letters to be considered for counting number of occurrences of the character 'a' in the infinite string. Returns: Total number of occurrences of the character 'a'. ''' # Length of string. len_str = len(s) # Number of repeated strings to be considered. num_strs = n//len_str # Remainder: Let's consider an example - s = 'abc' and n = 11. # Therefore, the string to be considered for finding the number # of occurrences of 'a' will be: 'abcabcabcab'. The string is # repeating 3 times(abcabcabc). Now, remaining letters are only 2(ab). # Therefore, length of remaining letters is calculated as below syntax. remainder = n%len_str # Counter to count number of a's from given string. count1 = 0 # Counter to count a's from the remaining set of letters. In the end, it # will be used to calculate total number of a's in the string. count2 = 0 for i in range(len_str): # Calculating number of occurrences of character 'a' from the given string if s[i] == 'a': count1 += 1 # Calculating number of occurrences from remaining letters # if they exist. if s[i] == 'a' and i < remainder: count2 += 1 # Calculating total number of a's in the string total = count1*num_strs + count2 return total # Testing print(repeatedString('aba', 10))