Sorting Algorithm Visualizer

A pygame-based visualizer for 15 sorting algorithms. Watch them sort in real time with live operation counts, seed-controlled arrays, and a post-sort verification sweep.

Algorithms

Key	Algorithm	Time Complexity	Space
1	Bogo Sort	O((n+1)!) avg ⚠️ use ≤8 bars	O(1)
2	Bubble Sort	O(n²)	O(1)
3	Bucket Sort	O(n+k) avg	O(n)
4	Cocktail Sort	O(n²)	O(1)
5	Comb Sort	O(n log n) avg	O(1)
6	Counting Sort	O(n+k)	O(k)
7	Heap Sort	O(n log n)	O(1)
8	Insertion Sort	O(n²)	O(1)
9	Intro Sort	O(n log n)	O(log n)
0	Merge Sort	O(n log n)	O(n)
Q	Quick Sort	O(n log n) avg	O(log n)
W	Radix Sort (LSD)	O(nk)	O(n+k)
E	Selection Sort	O(n²)	O(1)
A	Shell Sort	O(n²) worst, ~O(n^1.3) avg	O(1)
S	Tim Sort	O(n log n)	O(n)

Install

pip install pygame numpy

Run

# All 15 algorithms — switch with menu or keys (default)
python run.py

# Single algorithm
python run.py bubble

# Pick any combination
python run.py merge quick heap

# All algorithms racing side-by-side on the same array
python run.py --parallel

# Subset in parallel
python run.py --parallel bubble merge quick

# Full series — auto-advances through all algorithms
python run.py --series

# Start with a specific bar count
python run.py --bars 1000 bubble

# List all algorithm keys
python run.py --list

Controls

Key	Action
R	New random array, start sorting
Space	Pause / resume (or start after reset)
↑ / ↓	Speed up / slow down
[ / ]	Step through bar presets (resets, stays paused)
, / .	Seed − 1 / Seed + 1 (resets, stays paused)
T	Cycle colour theme (Color → B&W)
H	Toggle / hide bottom algorithm menu
1–9, 0	Jump to algorithm 1–10 (resets, stays paused)
Q W E A S	Jump to algorithm 11–15 (resets, stays paused)
Click	Select algorithm from bottom menu
Click Menu ▼	Toggle bottom menu (bottom-right button)

Note: Changing bars, seed, or algorithm resets the array but keeps it paused. Press R or Space to start sorting.

Bar count presets

Cycled with [ / ]:

100 → 200 → 300 → 400 → 500 → 1k → 2k → 3k → 4k → 5k → 10k → 20k → 30k → 40k → 50k → 60k → 70k → 80k → 90k → 100k

Speed levels

Cycled with ↑ / ↓:

2 → 4 → 8 → 16 → 32 → 64 → 128 → 256 → 512 → 1024 steps per frame

Seed control

Every run uses a seeded random array (default seed 42). Same seed + same algorithm + same bar count = identical array and identical stats every time. Use , / . to try different arrays without losing reproducibility.

Stats & verification

After sorting completes:

1. A white scan sweeps left → right verifying the array is sorted (with ascending sound)
2. A stats card appears in the centre showing:
   • Time taken (frozen at sort completion)
   • Comparisons (yellow)
   • Swaps (teal)
   • Writes / overwrites (blue)
   • Total operations (white)

Live counters (comparisons, swaps, writes, total ops) are always visible in the bottom-left corner during sorting.

Colour legend

Colour	Meaning
Pink	Unsorted bar
Yellow	Comparing
Teal	Swapping
Blue	Overwrite (merge / insertion / radix)
Green	Sorted / verified
White	Verification scan head

Project structure

├── algorithms/
│   ├── bogo_sort.py
│   ├── bubble_sort.py
│   ├── bucket_sort.py
│   ├── cocktail_shaker_sort.py
│   ├── comb_sort.py
│   ├── counting_sort.py
│   ├── heap_sort.py
│   ├── insertion_sort.py
│   ├── intro_sort.py
│   ├── merge_sort.py
│   ├── quick_sort.py
│   ├── radix_sort.py
│   ├── selection_sort.py
│   ├── shell_sort.py
│   └── tim_sort.py
├── core/
│   ├── constants.py   ← window size, colours, speed levels, bar presets
│   ├── sound.py       ← tone generation
│   ├── primitives.py  ← shared helpers (_merge, _heapify, _partition, …)
│   └── engine.py      ← pygame loop, run_visualizer / run_parallel / run_series
├── run.py             ← CLI entry point
└── run_all.py         ← shortcut to run all 15

Tuning

What	File	Setting
Window size	core/constants.py	WIDTH, HEIGHT = 1680, 900
Default bar count	core/constants.py	NUM_BARS = 100
Bar presets	core/constants.py	BAR_PRESETS list
Speed steps	core/constants.py	SPEED_LEVELS list
Bar colours / themes	core/constants.py	THEMES list
Default speed index	core/engine.py	speed_idx = 2
Default seed	core/engine.py	seed = 42
Sound pitch range	core/sound.py	300 + (value / MAX_VAL) * 900
Sound volume	core/sound.py	0.30 * 32767