Visualize Execution Live Programming Mode (NEW!)

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The examples below illustrate some of this tool's visualization capabilities but are not meant as standalone programming lessons. For effective learning, people often use this tool as a supplement to textbooks, lecture notes, and online programming tutorials.

Python Examples

Basic: hello | happy | intro | filter | tokenize | insertion sort | for-else | user input

Math: factorial | fibonacci | memoized fibonacci | square root | gcd | towers of hanoi

Objects: OOP 1 | OOP 2 | OOP 3 | inheritance

Linked Lists: LL 1 | LL 2 | LL sum

Pointer Aliasing:
aliasing1 | aliasing2 | aliasing3 | aliasing4 | aliasing5 | aliasing6 | aliasing7 | aliasing8 | sumList

Higher-Order Functions:
closure1 | closure2 | closure3 | closure4 | closure5 | list map | summation | lambda param

Advanced:
list comp | list/set/dict comp | decorator | generator | genexpr | varargs | exception | metaclass

Python 3 only: student torture | nonlocal

Java Examples

Basic: Variables | ControlFlow | Sqrt | ExecLimit | Strings

Methods: PassByValue | Recursion | StackOverflow

OOP: Rolex | Person | Complex | Casting

Data structures: LinkedList | StackQueue | Postfix | SymbolTable

Java features: ToString | Reflect | Exception | ExceptionFlow | TwoClasses

Misc: Forest | Knapsack | StaticInitializer | Synthetic

(All Java examples created by David Pritchard)

JavaScript Examples

factorial | data types | exception | closure | shadowing | constructor | inheritance

TypeScript Examples

hello | classes | inheritance | generics

Ruby Examples

Containers | Globals | Constants | Blocks | Block scoping | More block scoping

Proc & Lambda | Proc scoping | Proc return | Lambda scoping | Inheritance | Symbols

Protected & private | Class & instance vars | Toplevel defs | Megagreeter

C Examples

Thesis | Globals | Structs | Nested structs | Array overflow | Array param

String reverse | Pointer levels | Pointer chain | Pointers wild | Typedef

C++ Examples

Basic | Pass by ref | Class | Class pointer | Date class | Inheritance | Virtual method

Generate permanent link

Click the button above to create a permanent link to your visualization. To report a bug, paste the link along with a brief error description in an email addressed to philip@pgbovine.net

Python Tutor (code on GitHub) supports seven languages (despite its name!):

1. Python 2.7 and 3.3 with limited module imports and no file I/O. The following modules may be imported: bisect, collections, copy, datetime, functools, hashlib, heapq, itertools, json, math, operator, random, re, string, time, io/StringIO. Backend source code.

2. Java using Oracle's Java 8. The original Java visualizer was created by David Pritchard and Will Gwozdz. It supports StdIn, StdOut, most other stdlib libraries, Stack, Queue, and ST. (To access Java's built-in Stack/Queue classes, write import java.util.Stack; — note, import java.util.*; won't work.) Backend source code.

3. JavaScript running in Node.js v6.0.0 with limited support for ES6. Backend source code.

4. TypeScript 1.4.1 running in Node.js v6.0.0. Backend source code.

5. Ruby 2 using MRI 2.2.2. Backend source code.

6. C using gcc 4.8, C11, and Valgrind Memcheck. Backend source code.

7. C++ using gcc 4.8, C++11, and Valgrind Memcheck. Backend source code.

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Copyright © Philip Guo. All rights reserved.