Programming by Doing

“The best way to learn is to do.” - P.R. Halmos

 

If you've ever tried to teach yourself programming and couldn't quite get going, then these assignments are for you. Refined over fifteen years, these are the assignments I have used to teach the basics of Java to nearly 2,000 ordinary public school students over my career.

Buy My Books!

If you are having trouble figuring out how to do these assignments without help, then my book with videos “Learn Java the Hard Way” will explain things a lot better. (Especially if you have never coded before!)

Or if you have finished most of these assignments and are ready for the object-oriented side of Java, “Learn Object-Oriented Java the Hard Way” is the book for you!

If you have any questions about these assignments, please read the Frequently-Asked Questions at the bottom of this page.

Happy coding!
- Graham Mitchell

Last updated: Saturday, 2015-11-28

Basics and Printing - 9 assignments, 58 points
0	Basics and Printing	Installing the Java Development Kit (JDK)	20 points
1	Basics and Printing	Compiler Check	3 points
2	Basics and Printing	Compiling Practice	3 points
3	Basics and Printing	An Important Message	5 points
4	Basics and Printing	A Good First Program by Zed Shaw	4 points
5	Basics and Printing	Comments and Slashes by Zed Shaw	3 points
6	Basics and Printing	A Letter to Yourself	7 points
7	Basics and Printing	Your Initials	6 points
8	Basics and Printing	Numbers and Math by Zed Shaw	7 points
Variables - 5 assignments, 48 points
9	Variables	Variables and Names by Zed Shaw	7 points
10	Variables	More Variables and Printing by Zed Shaw	7 points
11	Variables	Using Variables	9 points
12	Variables	Still Using Variables	10 points
13	Variables	Your Schedule	15 points
Keyboard Input - 7 assignments, 106 points
14	Keyboard Input	Asking Questions by Zed Shaw	10 points
15	Keyboard Input	The Forgetful Machine	12 points
16	Keyboard Input	Name, Age, and Salary	15 points
17	Keyboard Input	More User Input of Data	16 points
18	Keyboard Input	Age in Five Years	18 points
19	Keyboard Input	A Dumb Calculator	20 points
20	Keyboard Input	BMI Calculator	15-28 points
If Statements - 17 assignments, 505 points
21	If Statements	What If by Zed Shaw	15 points
22	If Statements	How Old Are You?	25 points
23	If Statements	Else And If by Zed Shaw	20 points
24	If Statements	Weekday Name	15 points
25	If Statements	How Old Are You, Specifically?	20 points
26	If Statements	Space Boxing	30 points
27	If Statements	A Little Quiz	40 points
28	If Statements	Modulus Animation	20 points
GUIs - 3 assignments, 55 points
29	GUIs	Using Swing for Input	25 points
30	GUIs	A Boring Window	10 points
31	GUIs	A Frame with a Panel with Writing on It	20 points
32	If Statements	Twenty Questions... well, actually just Two	35 points
33	If Statements	Choose Your Own Short Adventure!	60 points
34	If Statements	Age Messages 3	25 points
35	If Statements	Two More Questions	35 points
36	If Statements	BMI Categories	35-45 points
37	If Statements	Gender Game	50 points
38	If Statements	compareTo() Challenge	35 points
39	If Statements	Alphabetical Order	30 points
40	If Statements	The Worst Number-Guessing Game Ever	15 points
Random Numbers - 8 assignments, 160 points
41	Random Numbers	Randomness	15 points
42	Random Numbers	Magic 8-Ball™	10 points
43	Random Numbers	A Number-Guessing Game	20 points
44	Random Numbers	Fortune Cookie	15-25 points
45	Random Numbers	Dice	25 points
46	Random Numbers	One Shot Hi-Lo	35 points
47	Random Numbers	Three-Card Monte	20 points
While Loops - 12 assignments, 500 points
48	While Loops	Enter Your PIN	15 points
49	While Loops	Keep Guessing	50 points
50	While Loops	Dice Doubles	45 points
51	While Loops	Counting with a While Loop	30 points
52	While Loops	PIN Lockout	10 points
53	While Loops	Number-Guessing with a Counter	40 points
54	While Loops	Hi-Lo with Limited Tries	55 points
55	While Loops	Adding Values in a Loop	30 points
Do-While Loops - 5 assignments, 130 points
56	Do-While Loops	Do-While Swimming	15 points
57	Do-While Loops	Flip Again?	20 points
58	Do-While Loops	Shorter Double Dice	40 points
59	Do-While Loops	Again with the Number-Guessing	35 points
60	While Loops	Safe Square Root	55 points
61	While Loops	Right Triangle Checker	65 points
62	While Loops	Collatz Sequence	30-60 points
63	While Loops	Short Adventure 2: With a Loop	75 points
63b	While Loops	Baby Nim	60 points
63c	While Loops	Nim	70-185 points
For Loops - 14 assignments, 335 points
64	For Loops	Counting with a For Loop	10 points
65	For Loops	Ten Times	15 points
66	For Loops	Counting Machine	20 points
67	For Loops	Counting Machine Revisited	25 points
68	For Loops	Counting by Halves	20 points
69	For Loops	Xs and Ys	15 points
70	For Loops	Noticing Even Numbers	30 points
71	For Loops	Fizz Buzz	40 points
72	For Loops	Letter at a Time	20 points
73	For Loops	For Loop Challenge	40 points
74	For Loops	Adding Values with a For Loop	30 points
75	Random Numbers	Baby Blackjack	20 points
Projects - 5 assignments, 860 points
76	Projects	Project: Blackjack	80-200 points
Graphics - 31 assignments, 1441 points
77	Graphics	Graphics Demo 1: Basics	20 points
78	Graphics	Graphics Demo 2: Arcs and Custom Colors	20 points
79	Graphics	Graphics Demo 3: Fonts and Lines	15 points
80	Graphics	A Circle	20 points
81	Graphics	A Smiling Face	40 points
82	Graphics	A Clock Face	50-70 points
83	Graphics	Graphing Lines	40 points
84	Graphics	Graphing Parabolas	40 points
85	Graphics	Graphics Demo 4: Polygons	40 points
86	Graphics	Drawing a Boring Triangle	30 points
87	Graphics	Drawing Random Triangles	60 points
88	Graphics	Drawing Random Right Triangles	80-140 points
89	Graphics	Sierpinski Triangle	150 points
90	Graphics	Boxy 1	50 points
91	Graphics	Boxy 2	40 points
92	Graphics	Boxy 3	60 points
93	Graphics	Smiling Face Function	80 points
94	Graphics	Forest and Trees	150 points
95	Graphics	Image Demo - Showing Images on the Screen	20 points
96	Graphics	Motivational Poster	50-80 points
Functions - 17 assignments, 1070 points
97	Functions	Picture Menu	10 points
98	Functions	Flicker Phrase	15 points
99	Functions	Heron's Formula	15 points
100	Functions	Distance Formula	50 points
101	Functions	Month Name	60 points
102	Functions	Month Offset	60 points
103	Functions	Weekday Calculator	90 points
104	Functions	Area Calculator	110 points
105	Functions	Function Call Alphabet	90 points
106	Functions	Fill-In Functions	100 points
107	Functions	More Fill-In Functions	100 points
108	Functions	Keychains for Saleby Aaron Gadberry	40 points
109	Functions	Keychains for Sale, for real this timeby Aaron Gadberry	65 points
110	Functions	Keychains for Sale, real ultimate powerby Aaron Gadberry	80 points
111	Functions	Calling Functions from Other Files	40 points
112	Functions	Evenness Function	60 points
113	Functions	Finding Prime Numbers	85 points
114	Do-While Loops	Baby Calculator	20 points
115	Projects	Project: Calculator	80-300 points
116	For Loops	A Refresher	20 points
117	For Loops	Refresher Challenge	20 points
118	For Loops	Displaying Some Multiples	30 points
Nested Loops - 9 assignments, 580 points
119	Nested Loops	Nesting Loops	20 points
120	Nested Loops	Odometer Loops	25 points
121	Nested Loops	Basic Nested Loops	50 points
122	Nested Loops	Multiplication Table	65 points
123	Nested Loops	Number Puzzle I	60 points
124	Nested Loops	Getting Individual Digits	80 points
125	Nested Loops	More Number Puzzles	100 points
126	Nested Loops	Number Puzzles III: Armstrong Numbers	90 points
127	Nested Loops	Number Puzzles IV: A New Hope	90 points
File Input and Output - 10 assignments, 535 points
128	File Input and Output	Letter Revisited	40 points
129	File Input and Output	High Score	50 points
130	File Input and Output	Simple File Input	40 points
131	File Input and Output	Summing Three Numbers from a File	50 points
132	File Input and Output	Summing Three Numbers from Any File	65 points
133	File Input and Output	Displaying a File	60 points
134	File Input and Output	Summing Several Numbers from Any File	60 points
135	File Input and Output	Simple Web Input	15 points
136	File Input and Output	A Little Puzzle	75 points
137	File Input and Output	Vowel Capitalization	80 points
Arrays - 16 assignments, 1245 points
138	Arrays	Basic Arrays 0	20 points
139	Arrays	Basic Arrays 1	30 points
140	Arrays	Basic Arrays 2	40 points
141	Arrays	Basic Arrays 3	25 points
142	Arrays	Copying Arrays	55 points
143	Arrays	Grades in an Array and a File	90 points
144	Arrays	Finding a Value in an Array	80 points
145	Arrays	How Many Times?	40 points
146	Arrays	Is It There or Not?	85 points
147	Arrays	Where Is It?	90 points
148	Arrays	Finding the Largest Value in an Array	100 points
149	Arrays	Locating the Largest Value in an Array	110 points
150	Arrays	Giving an Array a Bunch of Values at Once	30 points
151	Arrays	Parallel Arrays	100 points
152	Arrays	Tic-Tac-Toe	150 points
153	Arrays	Hangman	200 points
Sorting - 11 assignments, 1000 points
154	Sorting	MadLib Random	40 points
155	Sorting	Movie Title Generator	40 points
156	Sorting	PokéSwap	40 points
157	Sorting	PokéTrader	30 points
158	Sorting	PokéTrader 2	20 points
159	Sorting	Sorting an Array	100 points
160	Sorting	Exchange Sort	120 points
161	Sorting	Bubble Sort	130 points
162	Sorting	Selection Sort	130 points
Records - 11 assignments, 1070 points
163	Records	Web Addresses	30 points
164	Records	Web Addresses Array	10 points
165	Records	Address toString()	20 points
166	Records	Basic Records	80 points
167	Records	A Little Database	100 points
168	Records	A Little Database is shorter with a loop	100 points
169	Records	Getting Data from a File	120 points
170	Records	Getting More Data from a File	140 points
171	Records	Storing Data in a File	150 points
172	Records	Reading What You Wrote	160 points
173	Records	Sorting an Array of Records	160 points
174	Sorting	Sorting Strings	150 points
175	Sorting	Sorting Records on Two Fields	200 points
Objects - 1 assignment, 100 points
176	Objects	A Tic-Tac-Toe Class	100 points
ArrayLists - 14 assignments, 1165 points
177	ArrayLists	Basic ArrayLists 0	20 points
178	ArrayLists	Basic ArrayLists 1	30 points
179	ArrayLists	Basic ArrayLists 2	40 points
180	ArrayLists	Basic ArrayLists 3	25 points
181	ArrayLists	Copying ArrayLists	55 points
182	ArrayLists	Finding a Value in an ArrayList	80 points
183	ArrayLists	ArrayList - There or Not?	85 points
184	ArrayLists	ArrayList - Where Is It?	90 points
185	ArrayLists	Getting the Largest Value in an ArrayList	100 points
186	ArrayLists	Locating the Largest Value in an ArrayList	110 points
187	ArrayLists	Sorting an ArrayList	120 points
188	ArrayLists	Sorting an ArrayList of Strings	150 points
189	ArrayLists	Sorting Sentences	100 points
190	ArrayLists	Sorting an ArrayList of Records	160 points
191	Projects	Project: Address Book	200-400 points
192	Projects	Project: Hearts	300-500 points
Project Euler - 20 assignments, 1715 points
193	Project Euler	001 - Sum Multiples of 3 or 5	20 points
194	Project Euler	002 - Sum Even Fibonacci Numbers	40 points
195	Project Euler	003 - Largest Prime Factor of Big Number	60 points
196	Project Euler	004 - Largest Palindromic Product	70 points
197	Project Euler	005 - Smallest Divisible by 1-20	50 points
198	Project Euler	006 - Sums of Squares Minus Squares of Sums	50 points
199	Project Euler	007 - The 10001st Prime	80 points
200	Project Euler	008 - Largest Product of Consecutive Digits	100 points
201	Project Euler	009 - Pythagorean Triplet	75 points
202	Project Euler	010 - Sum of Primes Under Two Million	100 points
203	Project Euler	011 - Largest Product of 4 Numbers in Grid	160 points
204	Project Euler	012 - First Triangle Number w/501 Divisors	160 points
205	Project Euler	013 - Sum 100 Fifty-Digit Numbers	80 points
206	Project Euler	014 - Longest Collatz Sequence	150 points
207	Project Euler	015 - Routes Through a 20x20 Grid	100 points
208	Project Euler	016 - Sum of the Digits of 2^1000	50 points
209	Project Euler	017 - Letters in One to One Thousand	110 points
210	Project Euler	018 - Maximum Sum Path through Triangle	160 points
211	Project Euler	019 - Sundays on the 1st of the Month	50 points
212	Project Euler	020 - Sum of the Digits of 100!	50 points
213	Graphics	Mouse Demo	20 points
214	Graphics	Traffic Light - Drawing Shapes and Clicking Them	40 points
215	Graphics	Shapes Demo - Easily Drawing and Transforming Shapes	1 points
216	Graphics	Last Clicked - Drawing Boxes Where You Clicked	1 points
217	Graphics	No Erasey - Making Stuff Stay on the Screen	1 points
218	Graphics	Drag Location - Getting Drags instead of Clicks	1 points
219	Graphics	Drawing Layers	1 points
220	Graphics	Etch-A-Sketch	20 points
221	Graphics	Bouncing Ball	1 points
222	Graphics	Pong	100 points
223	Graphics	Reversi	200 points
224	Projects	Project: Paint	200-500 points

Frequently-Asked Questions

Can I email you for help?

No, sorry. There are thousands of you doing these assignments!

How can I get help?

There's forum on Reddit devoted just to the assignments on this site. Your question has probably been asked before, so check there! If you have a new question, upload your code to a Gist and then make a post. Someone will answer within a couple of days!

Are the solutions available?

No! Many teachers around the world use these assignments to teach their students. If answers were available some students would use them to cheat!

What if I buy your book? Are the solutions to these assignments in there?

Nope! My book is super great and you should totally buy it, but it will only teach you how to complete assignments like these.

It seems like some explanations are missing. Did you forget to upload something?

No, I didn't forget. Back in 2005, I didn't have any assignments to explain new concepts. I taught my students everything through lectures.

Then in 2010 I stopped lecturing and started creating "assignments" to replace my lectures. I got some of these completed, and you see them here. Students worked through the material at their own pace and asked me questions in person about anything that I hadn't gotten around to.

Finally, in 2013 I wrote “Learn Java the Hard Way”. Now students now use my book to learn each concept and then they use the rest of the assignments listed here to practice.

So the explanations for some of the later assignments (like File Input & Output) aren't "missing"; they never existed. Sorry for the inconvenience!