juniorStrings

How do you find the length of a string without built-in functions?

Updated Apr 28, 2026

Short answer

Iterate through characters and increment a counter until a null terminator or end-of-buffer is reached.

Deep explanation

Strings are one of the most common data types. Iterate through characters and increment a counter until a null terminator or end-of-buffer is reached. Understanding how they are represented (ASCII/UTF-8/UTF-16) is key to solving character encoding issues.

Real-world example

Storing user names or IDs in an application.

Common mistakes

  • Modifying a string inside a long loop without using a StringBuilder/StringBuffer.

Follow-up questions

  • What is the time complexity of concatenation?

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