String Rotation | Computer Science Algorithms

Introduction

In computer science, string rotation is a process of moving the characters in a string to the left or right. A string rotation of another string is a process of taking a string and moving its characters in a circular fashion. For example, the string "abcde" can be rotated to form the string "cdeab". In this challenge, we are going to determine if a string s1 is a rotation of another string s2.

Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL algorithm(("`Algorithm`")) -.-> algorithm/BasicAlgorithmsGroup(["`Basic Algorithms`"]) python(("`Python`")) -.-> python/BasicConceptsGroup(["`Basic Concepts`"]) python(("`Python`")) -.-> python/ControlFlowGroup(["`Control Flow`"]) python(("`Python`")) -.-> python/DataStructuresGroup(["`Data Structures`"]) python(("`Python`")) -.-> python/FunctionsGroup(["`Functions`"]) python(("`Python`")) -.-> python/ObjectOrientedProgrammingGroup(["`Object-Oriented Programming`"]) algorithm/BasicAlgorithmsGroup -.-> algorithm/recursion_dynamic("`Recursion Dynamic`") algorithm/BasicAlgorithmsGroup -.-> algorithm/arrays_strings("`Arrays Strings`") python/BasicConceptsGroup -.-> python/booleans("`Booleans`") python/ControlFlowGroup -.-> python/conditional_statements("`Conditional Statements`") python/DataStructuresGroup -.-> python/tuples("`Tuples`") python/FunctionsGroup -.-> python/function_definition("`Function Definition`") python/ObjectOrientedProgrammingGroup -.-> python/classes_objects("`Classes and Objects`") python/ObjectOrientedProgrammingGroup -.-> python/encapsulation("`Encapsulation`") python/FunctionsGroup -.-> python/build_in_functions("`Build-in Functions`") subgraph Lab Skills algorithm/recursion_dynamic -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} algorithm/arrays_strings -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} python/booleans -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} python/conditional_statements -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} python/tuples -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} python/function_definition -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} python/classes_objects -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} python/encapsulation -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} python/build_in_functions -.-> lab-268807{{"`Determine String Rotation in Computer Science`"}} end

Rotation

Problem

Given two strings s1 and s2, determine if s1 is a rotation of s2 by calling (only once) a function is_substring. The function is_substring takes two strings as input and returns True if the first string is a substring of the second string, and False otherwise.

Requirements

To solve this problem, we need to meet the following requirements:

The string is ASCII.
The comparison is case sensitive.
We can use additional data structures.
The strings can fit in memory.

Example Usage

Here are some examples of how the function should behave:

If the strings have different sizes, the function should return False.
If any of the strings is None, the function should return False.
If one of the strings is a space and the other is not, the function should return False.
If both strings are spaces, the function should return True.
If s1 is a rotation of s2, the function should return True.

Summary

In this challenge, we learned how to determine if a string is a rotation of another string by calling a function that checks if a string is a substring of another string. We also established the requirements for solving this problem and provided examples of how the function should behave.

Determine String Rotation in Computer Science