創建所有可能的組合-javascript

Question

很抱歉，如果這是重復的，但是我沒有找到解決問題的方法。 我有4組單詞，我需要創建4組的所有可能組合，但要保持組限制（即，每個組中必須有一個單詞，並且組中不能有重復）。

偽代碼示例：

Group1 = [A1, A2]
Group2 = [B1, B2]
Group3 = [C1, C2]
Group4 = [D1, D2]

Result:
A1 B1 C1 D1, 
A2 B1 C1 D1, 
A1 B2 C1 D1 ...

Unacceptable:
A1 A2 B1 C1, 
A1 B1 B2 C1

我什至不知道從哪里開始這樣的事情。 初始組是數組。

提前致謝。

Answer 1

這應該可以解決問題：

function cartesian() {
    var r = [], arg = arguments, max = arg.length-1; //r=results, arg=the arrays you sent, max=number of arrays you sent
    function helper(arr, i) {// this is a recursive function
        for (var j=0, l=arg[i].length; j<l; j++) { //for 0 to the current array's length
            var a = arr.slice(0); // clone array sent
            a.push(arg[i][j]) // add string
            if (i==max) { // reached 4 elements, add that as possibility
                r.push(a);
            } else // if its not 4, call recursive function sending the current possibility array and the following index of the array to choose from
                helper(a, i+1);
        }
    }
    helper([], 0); // this starts the recursive function, sending an empty array and index 0 (start with nothing from 0)
    return r; // after recursive function ends, return possibilities
};

Group1 = ["A1", "A2"]
Group2 = ["B1", "B2"]
Group3 = ["C1", "C2"]
Group4 = ["D1", "D2"]

console.log(cartesian(Group1,Group2,Group3,Group4));