String Character Counting | Dataford Interview Questions

Amagi Stream processes caption text and needs to measure how often a selected character appears. Given a string, a single-character target, and a case-sensitivity setting, return the number of matching occurrences.

Implement the function without using built-in substring-counting methods such as str.count().

Formal Specification

Input text: a string containing zero or more printable ASCII characters.
Input target: a string containing exactly one printable ASCII character.
Input case_sensitive: a Boolean. If True, only exact matches count. If False, uppercase and lowercase versions of the target are treated as equal.
Output: an integer representing the number of matching characters in text.

Each character is evaluated independently. For example, if target is "a" and matching is case-insensitive, both "a" and "A" contribute to the result.

Constraints

0 <= len(text) <= 10^6
target contains exactly one printable ASCII character
case_sensitive is either True or False
Every character in text is printable ASCII
Built-in substring-counting methods such as str.count() are not allowed

Function Signature

def count_character_occurrences(text, target, case_sensitive):

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