js數組排列

抽象問題：你面前有n個筐，每一個筐都放着不一樣數量的不一樣物品，讓你在每一個筐中拿一個物品，請問一共有多少可能，分別是什麼？

function combine(twoDimensionalArr) {

//二維數組中每一個數組的最大長度
var maxLengthArr = [];
//遍歷過程當中每一個數組的下標
var tempIndexArr = [];
for (var i = 0; i < twoDimensionalArr.length; i++) {
	maxLengthArr.push(twoDimensionalArr[i].length);
	tempIndexArr.push(0);
}
//組合一共有多少種
var count = 1;
for (var i = 0; i < maxLengthArr.length; i++) {
	count = count * maxLengthArr[i];
}

var combineValues = [];
var combineItem;
for (var i = 0; i < count; i++) {
	if (i !== 0) {
		var changeIndex = tempIndexArr.length - 1;
		var sholdAdd = false;
		while (!sholdAdd) {
			tempIndexArr[changeIndex] += 1;
			if (tempIndexArr[changeIndex] >= maxLengthArr[changeIndex]) {
				tempIndexArr[changeIndex--] = 0;
				sholdAdd = false;
			} else {
				sholdAdd = true
			}
		}
	}

	combineItem = [];
	for (var j = 0; j < tempIndexArr.length; j++) {
		combineItem.push(twoDimensionalArr[j][tempIndexArr[j]]);
	}
	combineValues.push(combineItem);
}
console.log(combineValues);
return combineValues;
}


combine([[1,2,3],["a","b","c","d"],["A","B"]]);`