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About C

Practice

77 contributors

1608 mentors

78,961
students have developed their C skills on Exercism.

Students

78,961

Submissions

628,101

Mentoring Discussions

7,005

The C track needs attention ⚠️

Building

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77 contributors

Build Test Runners

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Create Test Runners that have the single responsibility of taking a solution, running all tests and returning a standardized output.

Usage statistics

Total Test Runner Runs

584,304

Test Run Pass Rate

12.6% (73705)

Test Run Fail Rate

19.3% (113033)

Test Run Error Rate

68.0% (397566)

Build Analyzers

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Build an Analyzer for C: Exercism's analyzers automatically assess student's submissions and provide mentor-style commentary.

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Build Representers

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Build a Representer: a bit of code that has the single responsibility of taking a solution and returning a normalized representation of it.

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Create Practice Exercises

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Practice Exercises are exercises designed to allow students to solve an arbitrary problem, with the aim of them making use of the concepts they have learned so far.

Next goal: Implement 130 practice exercises. Find out more.

Usage statistics

73 active practice exercises

Started

Attempts

Completions

Mentoring requests

Hello World

55,538

207,971 (avg. 3.7)

22,546 (40.6%)

20 (0.0%)

Armstrong Numbers

15,576

82,918 (avg. 5.3)

6,554 (42.1%)

1,499 (9.6%)

Isogram

6,968

59,851 (avg. 8.6)

3,901 (56.0%)

1,332 (19.1%)

Hamming

3,571

16,343 (avg. 4.6)

2,887 (80.8%)

534 (15.0%)

Grains

3,113

20,732 (avg. 6.7)

2,469 (79.3%)

418 (13.4%)

Difference of Squares

2,611

11,147 (avg. 4.3)

2,214 (84.8%)

295 (11.3%)

Square Root

2,185

8,116 (avg. 3.7)

1,477 (67.6%)

198 (9.1%)

Grade School

1,730

16,680 (avg. 9.6)

721 (41.7%)

140 (8.1%)

Binary Search

1,978

16,035 (avg. 8.1)

1,308 (66.1%)

178 (9.0%)

Rational Numbers

898

7,588 (avg. 8.4)

541 (60.2%)

75 (8.4%)

Circular Buffer

1,078

8,686 (avg. 8.1)

519 (48.1%)

75 (7.0%)

List Ops

956

6,566 (avg. 6.9)

514 (53.8%)

63 (6.6%)

Reverse String

419

3,614 (avg. 8.6)

315 (75.2%)

17 (4.1%)

Resistor Color

5,596

33,751 (avg. 6.0)

2,780 (49.7%)

626 (11.2%)

Pythagorean Triplet

757

3,640 (avg. 4.8)

362 (47.8%)

38 (5.0%)

Saddle Points

552

2,917 (avg. 5.3)

307 (55.6%)

31 (5.6%)

Allergies

727

2,746 (avg. 3.8)

491 (67.5%)

40 (5.5%)

Phone Number

619

4,245 (avg. 6.9)

391 (63.2%)

42 (6.8%)

Clock

728

3,375 (avg. 4.6)

445 (61.1%)

36 (4.9%)

Sieve

672

2,922 (avg. 4.3)

475 (70.7%)

33 (4.9%)

Robot Simulator

708

2,182 (avg. 3.1)

468 (66.1%)

39 (5.5%)

Pascal's Triangle

597

2,223 (avg. 3.7)

368 (61.6%)

34 (5.7%)

Binary

801

5,063 (avg. 6.3)

610 (76.2%)

41 (5.1%)

Queen Attack

482

1,580 (avg. 3.3)

367 (76.1%)

28 (5.8%)

Linked List

801

5,230 (avg. 6.5)

410 (51.2%)

73 (9.1%)

Darts

1,897

3,696 (avg. 1.9)

1,303 (68.7%)

70 (3.7%)

Resistor Color Duo

1,119

1,967 (avg. 1.8)

831 (74.3%)

19 (1.7%)

Resistor Color Trio

937

2,342 (avg. 2.5)

686 (73.2%)

19 (2.0%)

Acronym

1,880

6,937 (avg. 3.7)

1,233 (65.6%)

109 (5.8%)

Gigasecond

1,266

1,731 (avg. 1.4)

932 (73.6%)

131 (10.3%)

Space Age

961

2,107 (avg. 2.2)

726 (75.5%)

22 (2.3%)

High Scores

168

1,053 (avg. 6.3)

125 (74.4%)

7 (4.2%)

Pangram

1,184

3,817 (avg. 3.2)

874 (73.8%)

44 (3.7%)

Word Count

1,460

2,805 (avg. 1.9)

668 (45.8%)

190 (13.0%)

Rail Fence Cipher

310

1,343 (avg. 4.3)

200 (64.5%)

8 (2.6%)

Matching Brackets

613

1,993 (avg. 3.3)

409 (66.7%)

51 (8.3%)

Nucleotide Count

705

3,571 (avg. 5.1)

499 (70.8%)

19 (2.7%)

RNA Transcription

788

2,310 (avg. 2.9)

589 (74.7%)

33 (4.2%)

Secret Handshake

427

2,112 (avg. 4.9)

291 (68.1%)

15 (3.5%)

Meetup

596

874 (avg. 1.5)

305 (51.2%)

9 (1.5%)

Pig Latin

274

1,595 (avg. 5.8)

168 (61.3%)

8 (2.9%)

Leap

1,054

2,495 (avg. 2.4)

855 (81.1%)

21 (2.0%)

Two Fer

471

1,424 (avg. 3.0)

365 (77.5%)

13 (2.8%)

Beer Song

675

2,235 (avg. 3.3)

433 (64.1%)

112 (16.6%)

Raindrops

662

1,495 (avg. 2.3)

513 (77.5%)

19 (2.9%)

Roman Numerals

737

10,927 (avg. 14.8)

475 (64.5%)

67 (9.1%)

Wordy

267

1,072 (avg. 4.0)

163 (61.0%)

11 (4.1%)

Bob

633

2,627 (avg. 4.2)

449 (70.9%)

17 (2.7%)

Complex Numbers

364

914 (avg. 2.5)

274 (75.3%)

3 (0.8%)

Sum of Multiples

528

1,225 (avg. 2.3)

337 (63.8%)

9 (1.7%)

Two Bucket

167

477 (avg. 2.9)

97 (58.1%)

0 (0.0%)

Anagram

518

1,431 (avg. 2.8)

337 (65.1%)

14 (2.7%)

Binary Search Tree

405

1,758 (avg. 4.3)

212 (52.3%)

29 (7.2%)

Say

219

781 (avg. 3.6)

118 (53.9%)

3 (1.4%)

ETL

284

1,108 (avg. 3.9)

181 (63.7%)

7 (2.5%)

Series

389

1,400 (avg. 3.6)

235 (60.4%)

4 (1.0%)

Diamond

273

942 (avg. 3.5)

176 (64.5%)

6 (2.2%)

Minesweeper

281

922 (avg. 3.3)

155 (55.2%)

6 (2.1%)

Run-Length Encoding

254

1,110 (avg. 4.4)

146 (57.5%)

7 (2.8%)

Atbash Cipher

353

1,147 (avg. 3.2)

234 (66.3%)

30 (8.5%)

Crypto Square

216

766 (avg. 3.5)

130 (60.2%)

0 (0.0%)

React

568

2,510 (avg. 4.4)

129 (22.7%)

18 (3.2%)

Prime Factors

310

772 (avg. 2.5)

198 (63.9%)

4 (1.3%)

Nth Prime

382

1,060 (avg. 2.8)

238 (62.3%)

5 (1.3%)

Perfect Numbers

317

957 (avg. 3.0)

228 (71.9%)

2 (0.6%)

Triangle

461

1,751 (avg. 3.8)

289 (62.7%)

8 (1.7%)

Collatz Conjecture

404

1,291 (avg. 3.2)

314 (77.7%)

25 (6.2%)

Luhn

326

1,960 (avg. 6.0)

212 (65.0%)

14 (4.3%)

Palindrome Products

279

1,022 (avg. 3.7)

142 (50.9%)

11 (3.9%)

All Your Base

338

1,081 (avg. 3.2)

180 (53.3%)

6 (1.8%)

Scrabble Score

306

969 (avg. 3.2)

217 (70.9%)

16 (5.2%)

Sublist

267

879 (avg. 3.3)

150 (56.2%)

8 (3.0%)

Largest Series Product

310

1,219 (avg. 3.9)

199 (64.2%)

4 (1.3%)

57 unimplemented practice exercises

Affine Cipher

Alphametics

Bank Account

Book Store

Bottle Song

Bowling

Change

Connect

Custom Set

D&D Character

DOT DSL

Dominoes

Error Handling

Flatten Array

Food Chain

Forth

Go Counting

Grep

Hangman

House

ISBN Verifier

Killer Sudoku Helper

Kindergarten Garden

Knapsack

Ledger

Lens Person

Markdown

Matrix

Micro Blog

OCR Numbers

POV

PaaS I/O

Parallel Letter Frequency

Poker

Protein Translation

Proverb

REST API

Rectangles

Robot Name

Rotational Cipher

SGF Parsing

Satellite

Scale Generator

Simple Cipher

Simple Linked List

Spiral Matrix

State of Tic-Tac-Toe

Strain

Tournament

Transpose

Tree Building

Twelve Days

Variable Length Quantity

Word Search

Yacht

Zebra Puzzle

Zipper

Volunteers

280

siebenschlaefer

6,582

ryanplusplus

3,856

bobahop

3,832

+ 268 more

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78,961 students have developed their C skills on Exercism.

The C track needs attention ⚠️

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Usage statistics

We 💙 our volunteers

78,961
students have developed their C skills on Exercism.