=====Problem ========

Yesterday you found some shoes in the back of your closet. Each shoe is described by two values:

type indicates if it's a left or a right shoe; size is the size of the shoe. Your task is to check whether it is possible to pair the shoes you found in such a way that each pair consists of a right and a left shoe of an equal size.

Example

For

shoes = [[0, 21], [1, 23], [1, 21], [0, 23]] the output should be solution(shoes) = true;

For

shoes = [[0, 21], [1, 23], [1, 21], [1, 23]] the output should be solution(shoes) = false.

Input/Output

[execution time limit] 4 seconds (js)

[input] array.array.integer shoes

Array of shoes. Each shoe is given in the format [type, size], where type is either 0 or 1 for left and right respectively, and size is a positive integer.

Guaranteed constraints: 1 ≤ shoes.length ≤ 200, 1 ≤ shoes[i][1] ≤ 100.

[output] boolean

true if it is possible to pair the shoes, false otherwise.

===== Solutions ========.

function solution(shoes) { const pairs = shoes.reduce((pairs, shoe) => { const [type, size] = shoe; pairs[size] = (pairs[size] || 0) + (type ? +1 : -1); return pairs; }, {}); return !Object.values(pairs).some(value => value); }

===== Solution 2========

function solution(shoes) { const result = shoes.reduce((acc, [side, size]) => { const action = side ? 1 : -1 console.log("actions", action);

acc[size] ? acc[size] += action : acc[size] = action console.log(acc) return acc; }, {});

return Object .values(result) .every((item) => item === 0); }

console.log(solution([[0, 21], [1, 23], [1, 21], [0, 23]]));