Kumite

Start a new Kumite

Kumite (ko͞omiˌtā) is the practice of taking techniques learned from Kata and applying them through the act of freestyle sparring.

You can create a new kumite by providing some initial code and optionally some test cases. From there other warriors can spar with you, by enhancing, refactoring and translating your code. There is no limit to how many warriors you can spar with.

A great use for kumite is to begin an idea for a kata as one. You can collaborate with other code warriors until you have it right, then you can convert it to a kata.

AlexWDvs.woodywang

NumSum

Code

Diff

function numSum(num){
  return (num * (num + 1)) / 2;
}

- function numSum(num){
- ~~var sum = 0;~~
- ~~for (var i = 1; i <= num; i++) {~~
- sum += i
- }
- ~~return sum~~
- return (num * (num + 1)) / 2;
- }

ashvinvs.JABirchall

Calculate token cost from a given price and delimiter

Mathematics

Algorithms

Logic

Numbers

Test Cases

Diff

// PHPUnit Test Examples:
// TODO: Replace examples and use TDD development by writing your own tests
class MyTestCases extends TestCase
{
    // test function names should start with "test"
    public function testThatSomethingShouldHappen() {
      $this->assertEquals("a", "a");
      $this->assertEquals([0], [0]);
    }
}

- // PHPUnit Test Examples:
- // TODO: Replace examples and use TDD development by writing your own tests
- class MyTestCases extends TestCase
- {
- // test function names should start with "test"
- public function testThatSomethingShouldHappen() {
- $this->assertEquals("a", "a");
- $this->assertEquals([0], [0]);
- }
- }

PVGradvs.PVGrad

Ping pong next serve

Games

Fundamentals

Basic Language Features

Code

Diff

const whoShouldServe = (scoreLeft, scoreRight, servesCount) => {
  return Math.floor((scoreLeft + scoreRight) / servesCount) % 2 === 0 ? 'first' : 'second';
};

- function whoShouldServe($scoreLeft, $scoreRight, $servesCount) {
- ~~return floor(($scoreLeft + $scoreRight) / $servesCount) % 2 === 0 ? 'first' : 'second';~~
- const whoShouldServe = (scoreLeft, scoreRight, servesCount) => {
- return Math.floor((scoreLeft + scoreRight) / servesCount) % 2 === 0 ? 'first' : 'second';
- };

Test Cases

Diff

describe("Solution", function(){
  it("Basic tests", function(){
    a = whoShouldServe(0, 0, 2);
    Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
    assert.strictEqual(a, 'first');
    a = whoShouldServe(1, 0, 2);
    Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
    assert.strictEqual(a, 'first');
    a = whoShouldServe(1, 2, 2);
    Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
    assert.strictEqual(a, 'second');
    a = whoShouldServe(1, 3, 2);
    Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
    assert.strictEqual(a, 'first');
    a = whoShouldServe(7, 8, 2);
    Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
    assert.strictEqual(a, 'second');
    a = whoShouldServe(7, 8, 5);
    Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
    assert.strictEqual(a, 'second');
    a = whoShouldServe(0, 6, 5);
    Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
    assert.strictEqual(a, 'second');
    a = whoShouldServe(1, 10, 5);
    Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
    assert.strictEqual(a, 'first');
  });

  const whoIs = (scoreLeft, scoreRight, servesCount) => Math.floor((scoreLeft + scoreRight) / servesCount) % 2 === 0 ? 'first' : 'second';
  const getRandomInt = (min, max) => Math.floor(Math.random() * (max - min)) + min;

  it("Random tests", function(){
    scoreLeft = getRandomInt(1, 12);
    scoreRight = getRandomInt(1, 12);
    a = whoShouldServe(scoreLeft, scoreRight, 2);
    Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
    assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
    scoreLeft = getRandomInt(1, 12);
    scoreRight = getRandomInt(1, 12);
    a = whoShouldServe(scoreLeft, scoreRight, 2);
    Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
    assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
    scoreLeft = getRandomInt(1, 12);
    scoreRight = getRandomInt(1, 12);
    a = whoShouldServe(scoreLeft, scoreRight, 2);
    Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
    assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
    scoreLeft = getRandomInt(1, 12);
    scoreRight = getRandomInt(1, 12);
    a = whoShouldServe(scoreLeft, scoreRight, 2);
    Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
    assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
    scoreLeft = getRandomInt(1, 12);
    scoreRight = getRandomInt(1, 12);
    a = whoShouldServe(scoreLeft, scoreRight, 2);
    Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
    assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
  });
});

- class EqualsTest extends TestCase
- {
- public function testBasic()
- {
- ~~$a = whoShouldServe(0, 0, 2);~~
- $this->assertEquals($a, 'first');
- ~~$a = whoShouldServe(1, 0, 2);~~
- $this->assertEquals($a, 'first');
- ~~$a = whoShouldServe(1, 2, 2);~~
- $this->assertEquals($a, 'second');
- ~~$a = whoShouldServe(1, 3, 2);~~
- $this->assertEquals($a, 'first');
- ~~$a = whoShouldServe(7, 8, 2);~~
- $this->assertEquals($a, 'second');
- ~~$a = whoShouldServe(7, 8, 5);~~
- $this->assertEquals($a, 'second');
- ~~$a = whoShouldServe(0, 6, 5);~~
- $this->assertEquals($a, 'second');
- ~~$a = whoShouldServe(1, 10, 5);~~
- $this->assertEquals($a, 'first');
- }
- protected function whoIs($scoreLeft, $scoreRight, $servesCount) {
- return floor(($scoreLeft + $scoreRight) / $servesCount) % 2 === 0 ? 'first' : 'second';
- }
- public function testRandom()
- {
- ~~$scoreLeft = rand(1, 11);~~
- ~~$scoreRight = rand(1, 11);~~
- ~~$a = whoShouldServe($scoreLeft, $scoreRight, 2);~~
- $this->assertEquals($a, $this->whoIs($scoreLeft, $scoreRight, 2));
- ~~$scoreLeft = rand(1, 11);~~
- ~~$scoreRight = rand(1, 11);~~
- ~~$a = whoShouldServe($scoreLeft, $scoreRight, 2);~~
- $this->assertEquals($a, $this->whoIs($scoreLeft, $scoreRight, 2));
- ~~$scoreLeft = rand(1, 11);~~
- ~~$scoreRight = rand(1, 11);~~
- ~~$a = whoShouldServe($scoreLeft, $scoreRight, 2);~~
- $this->assertEquals($a, $this->whoIs($scoreLeft, $scoreRight, 2));
- ~~$scoreLeft = rand(1, 11);~~
- ~~$scoreRight = rand(1, 11);~~
- ~~$a = whoShouldServe($scoreLeft, $scoreRight, 2);~~
- $this->assertEquals($a, $this->whoIs($scoreLeft, $scoreRight, 2));
- ~~$scoreLeft = rand(1, 11);~~
- ~~$scoreRight = rand(1, 11);~~
- ~~$a = whoShouldServe($scoreLeft, $scoreRight, 2);~~
- $this->assertEquals($a, $this->whoIs($scoreLeft, $scoreRight, 2));
- }
- }
- describe("Solution", function(){
- it("Basic tests", function(){
- a = whoShouldServe(0, 0, 2);
- Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
- assert.strictEqual(a, 'first');
- a = whoShouldServe(1, 0, 2);
- Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
- assert.strictEqual(a, 'first');
- a = whoShouldServe(1, 2, 2);
- Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
- assert.strictEqual(a, 'second');
- a = whoShouldServe(1, 3, 2);
- Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
- assert.strictEqual(a, 'first');
- a = whoShouldServe(7, 8, 2);
- Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
- assert.strictEqual(a, 'second');
- a = whoShouldServe(7, 8, 5);
- Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
- assert.strictEqual(a, 'second');
- a = whoShouldServe(0, 6, 5);
- Test.assertEquals(a, 'second', "expected: 'second' got: " + a);
- assert.strictEqual(a, 'second');
- a = whoShouldServe(1, 10, 5);
- Test.assertEquals(a, 'first', "expected: 'first' got: " + a);
- assert.strictEqual(a, 'first');
- });
- const whoIs = (scoreLeft, scoreRight, servesCount) => Math.floor((scoreLeft + scoreRight) / servesCount) % 2 === 0 ? 'first' : 'second';
- const getRandomInt = (min, max) => Math.floor(Math.random() * (max - min)) + min;
- it("Random tests", function(){
- scoreLeft = getRandomInt(1, 12);
- scoreRight = getRandomInt(1, 12);
- a = whoShouldServe(scoreLeft, scoreRight, 2);
- Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
- assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
- scoreLeft = getRandomInt(1, 12);
- scoreRight = getRandomInt(1, 12);
- a = whoShouldServe(scoreLeft, scoreRight, 2);
- Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
- assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
- scoreLeft = getRandomInt(1, 12);
- scoreRight = getRandomInt(1, 12);
- a = whoShouldServe(scoreLeft, scoreRight, 2);
- Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
- assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
- scoreLeft = getRandomInt(1, 12);
- scoreRight = getRandomInt(1, 12);
- a = whoShouldServe(scoreLeft, scoreRight, 2);
- Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
- assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
- scoreLeft = getRandomInt(1, 12);
- scoreRight = getRandomInt(1, 12);
- a = whoShouldServe(scoreLeft, scoreRight, 2);
- Test.assertEquals(a, whoIs(scoreLeft, scoreRight, 2), "expected: " + whoIs(scoreLeft, scoreRight, 2) + " got: " + a);
- assert.strictEqual(a, whoIs(scoreLeft, scoreRight, 2));
- });
- });

jakubneubauervs.thomascfoulds

Failed Tests

Add Directories to PATH Without Duplicates

Bash

Code

Diff

add_PATH() {
    echo -n "$PATH:$1" | awk 'BEGIN{RS=":";ORS=""}!x[$0]++{if(SEP){print ":"}print $0;SEP=1}'
}

echo "Original Path: $PATH"
export PATH=$(add_PATH /usr/local/bin2)
echo "New Path:      $PATH"

- add_PATH() {
- ~~t=$(echo $PATH | tr : '\n' | awk '!x[$0]++' | tr '\n' : | sed 's/.$//')~~
- ~~echo -n "$t"~~
- ~~unset t~~
- echo -n "$PATH:$1" | awk 'BEGIN{RS=":";ORS=""}!x[$0]++{if(SEP){print ":"}print $0;SEP=1}'
- }
- echo "Original Path: $PATH"
- ~~export PATH=$(add_PATH /usr/local/bin)~~
- ~~echo "New Path: $PATH"~~
- export PATH=$(add_PATH /usr/local/bin2)
- echo "New Path: $PATH"

DisruptiveMindvs.DisruptiveMind

Memoize

Functions

Control Flow

Basic Language Features

Fundamentals

This solution uses a simple hash for holding stringified args to quickly lookup the cache.

The assumption is that only one type of function signature is ever used.

Test Cases

Diff

describe("Solution", function(){
  var called = 0;
  
  function sum(a, b) {
    called++;
    
    return a + b;
  }
   
  it("should add 1 + 2", function(){
    Test.assertEquals(memoize(sum)(1,2), 3);
  });
  
  it("should have been called once", function(){
    Test.assertEquals(called, 1);
  });
  
  it("should still have been called once due to cache", function(){
    memoize(sum)(1,2)
    Test.assertEquals(called, 1);
  });
  
  it("should still have been called twice if different param orders", function(){
    memoize(sum)(2,1)
    Test.assertEquals(called, 2);
  });
  
});

- describe("Solution", function(){
- var called = 0;
- function sum(a, b) {
- called++;
- return a + b;
- }
- it("should add 1 + 2", function(){
- Test.assertEquals(memoize(sum)(1,2), 3);
- });
- it("should have been called once", function(){
- Test.assertEquals(called, 1);
- });
- it("should still have been called once due to cache", function(){
- memoize(sum)(1,2)
- Test.assertEquals(called, 1);
- });
- it("should still have been called twice if different param orders", function(){
- memoize(sum)(2,1)
- Test.assertEquals(called, 2);
- });
- });

theGerkvs.i00lii

Basic Power Function

Fundamentals

Code

Diff

using System.Numerics;

public class basic 
{
		public static BigInteger pow(long down, ulong up)
		{
			BigInteger output = 1;
			BigInteger cumulativeDown = down;

			for(ulong bitChecker = 1; bitChecker > 0 && bitChecker <= up; bitChecker <<= 1)
			{
				if((bitChecker & up) != 0)
				{
					output *= cumulativeDown;
				}

				cumulativeDown *= cumulativeDown;
			}

			return output;
		}
}

- using System.Numerics;
- public class basic
- {
- ~~public static BigInteger pow(long down, long up)~~
- ~~=> up == 0 ? 1 : down * pow(down, up - 1);~~
- public static BigInteger pow(long down, ulong up)
- {
- BigInteger output = 1;
- BigInteger cumulativeDown = down;
- for(ulong bitChecker = 1; bitChecker > 0 && bitChecker <= up; bitChecker <<= 1)
- {
- if((bitChecker & up) != 0)
- {
- output *= cumulativeDown;
- }
- cumulativeDown *= cumulativeDown;
- }
- return output;
- }
- }

user6225491vs.hiseni

It's all about space!

Code

Diff

```
let spaceMaker=str=>[...str].join(' ');
```
- function spaceMaker(str) {
- ~~return str.split("").join(" ");~~
- }
- let spaceMaker=str=>[...str].join(' ');

Demkivs.dinglemouse

Return Largest Possible Number

Code

Diff

import java.util.stream.*;

class Solution {

  public static String largestNumber(final Integer[] nums) {
    return Stream.of(nums)
      .sorted((a,b)->(""+b+a).compareTo(""+a+b))
      .collect(Collectors.reducing("",(x)->""+x,String::concat));
  }
}

- import java.util.stream.*;
- class Solution {
- public static String largestNumber(final Integer[] nums) {
- return Stream.of(nums)
- .sorted((a,b)->(""+b+a).compareTo(""+a+b))
- ~~.map(n->""+n)~~
- ~~.collect(Collectors.joining());~~
- .collect(Collectors.reducing("",(x)->""+x,String::concat));
- }
- }

Freestyle Sparring

NumSum

Calculate token cost from a given price and delimiter

Ping pong next serve

Add Directories to PATH Without Duplicates

Memoize

Basic Power Function

It's all about space!

Return Largest Possible Number

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Freestyle Sparring

Confirm

Collect: kata

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