Introduction to sorting - Programming Language C++ for Competitive Programming

Module 1: Introduction to Programming

What is Programming?
Why Do We Need Programming?
Setting Up Development Environment

Module 2: Your First Program

Hello World Program
Program Structure
Problems

Module 3: Input/Output and Arithmetic Operators

Data Input/Output
Arithmetic Operators
Problems

Module 4: Conditional Statements

Comparison Operators
Conditional Operators
Problems
Problems

Module 5: Data Types

Data Types
Problems
Problems
Problems
Problems

Module 6: Loops

The For Loop
Loop Patterns
Problems
Problems
Problems
Problems

Module 7: Arrays

Array Definition
Multi-dimensional arrays
Problems
Problems

Module 8: Functions

Functions
Problems for practice

Module 9: Nested loops and Multi-dimensional array

Nested Loops and Multi-Dimensional Arrays
Problems for practice

Module 10: Linear Search

Linear Search
Problems

Module 11: STL Data Structures 1

STL Data Structures
Problems for practice

Module 12: Basic Sorting Algorithms

Introduction to sorting
Bubble Sort
Selection Sort
Insertion Sort
Problems for practice

Module 13: STL Data Structures 2

STL Data Structures: set and map
Problems for practice

Module 14: Brute-forces

Introduction to bruteforce
Problems for practice

Module 15: Recursion

Introduction to Recursion
Problems for practice

Module 16: Structs in C++

Structs

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Home/Courses/Programming Language C++ for Competitive Programming/Module 12: Basic Sorting Algorithms/Introduction to sorting

Introduction to sorting

What algorithms exist for sorting algorithms?

Introduction to Sorting Algorithms

Sorting algorithms are methods used to arrange data in a specific order (usually ascending or descending).

Let's look into classical problem statement:

Given an array $A$ of $N$ elements, rearrange them so that $A[1] \leq A[2] \leq \ldots \leq A[N]$ (or in descending order).

A valid solution must:

Reorder elements (not change their values)

Up next

Bubble Sort

Bubble sort algorithm

Produce a fully sorted sequence

Do so with correctness and ideally efficiency

Where Sorting Algorithms Are Helpful

Sorting is a foundational tool in computer science and appears in many real tasks:

Binary search requires sorted data
Many dynamic programming and greedy algorithms sort first
Ranking students by scores
Detecting duplicates (after sorting, equal items are adjacent)
Sorting points by x-coordinate
Sorting edges by weight (e.g., Kruskal’s MST algorithm)
Sorting tasks by deadlines or durations

Simple Sorting Algorithms

Bubble Sort — swaps adjacent elements if they’re wrong.
Selection Sort — picks the smallest element and places it correctly.
Insertion Sort — inserts each element into its correct position in the sorted prefix.