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.

k.dmitriy.a@gmail.comvs.user9015794

This number is even or odd?

Code

Diff

def even_or_odd(n):
    return ("Even", "Odd")[n % 2]

- def even_or_odd(n):
- ~~return ["Even", "Odd"][n % 2]~~
- return ("Even", "Odd")[n % 2]

k.dmitriy.a@gmail.comvs.user9015794

Check Even Number

Code

Diff

```
is_even = lambda x: not x & 1
```
- ~~is_even = lambda x: not(x % 2)~~
- is_even = lambda x: not x & 1

Test Cases

Diff

import codewars_test as test
import solution

@test.describe('Test')
def test_group():
    @test.it('Even case')
    def is_even():
        for i in range(-30, 30, 2):
            test.assert_equals(solution.is_even(i), True)
            
    @test.it('Odd case')
    def is_even():
        for i in range(-29, 30, 2):
            test.assert_equals(solution.is_even(i), False)

- import codewars_test as test
- import solution
- @test.describe('Test')
- def test_group():
- @test.it('Even case')
- def is_even():
- ~~for i in range(0, 30, 2):~~
- for i in range(-30, 30, 2):
- test.assert_equals(solution.is_even(i), True)
- @test.it('Odd case')
- def is_even():
- ~~for i in range(1, 30, 2):~~
- for i in range(-29, 30, 2):
- test.assert_equals(solution.is_even(i), False)

k.dmitriy.a@gmail.comvs.monkey_on_a_keyboard_1

double value: binary except I have trouble with using 2's complement

Code

Diff

import java.lang.Math;
interface Kata {
  static int doubleValue(int x) {
    boolean isNeg=x<0;
    if (isNeg){
      x= -x;
    }
    x=x+x;
    StringBuilder b= new StringBuilder();
    while (x!=0){
      b.append(x%2==0?"h":"a-");
      x=x/2;
    }
    b=b.reverse();
    String s=b.toString().replaceAll("-", "");
    int curr=s.length()-1;
    int acc=0;
    int i=0;
    while (i<s.length()){
      acc+= s.charAt(i)=='a'? (int) Math.pow(2,curr):0;
      i++;
      curr--;
    }
    return isNeg?-acc:acc;
  }
}

- import java.lang.Math;
- interface Kata {
- static int doubleValue(int x) {
- boolean isNeg=x<0;
- if (isNeg){
- x= -x;
- }
- x=x+x;
- StringBuilder b= new StringBuilder();
- while (x!=0){
- ~~b.append(x%2==0?"0":"1");~~
- b.append(x%2==0?"h":"a-");
- x=x/2;
- }
- b=b.reverse();
- ~~String s=b.toString();~~
- String s=b.toString().replaceAll("-", "");
- int curr=s.length()-1;
- int acc=0;
- int i=0;
- while (i<s.length()){
- ~~acc+= s.charAt(i)=='1'? (int) Math.pow(2,curr):0;~~
- acc+= s.charAt(i)=='a'? (int) Math.pow(2,curr):0;
- i++;
- curr--;
- }
- return isNeg?-acc:acc;
- }
- }