How to generate fully combinations of multiple arrays?
const source = [ ["a", "b", "c"], ["d", "e", "f"], ["g", "h", "i"] ]; const result = combination(source); Need result, like a cartesian product, but with combinations of all sizes:
["a"] ["a", "d"] ["a", "d", "g"] ... ["b"] ... ["b", "f", "i"] ... ["i"] How about this:
function cartesianProduct(arrArr) { if (arrArr.length === 0) return []; const [firstArr, ...restArrs] = arrArr; const partialProducts = cartesianProduct(restArrs || []); let ret = firstArr.map(elem => [elem]); ret = ret.concat(partialProducts); ret = ret.concat(partialProducts.reduce((acc, product) => { return acc.concat(firstArr.map(elem => [elem].concat(product))); }, [])); return ret; } 