Creates a new array out of the two supplied by creating each possible pair from the arrays.
Use Array.prototype.reduce(), Array.prototype.map() and Array.prototype.concat() to produce every possible pair from the elements of the two arrays and save them in an array.
代码片段
const xProd = (a, b) => a.reduce((acc, x) => acc.concat(b.map(y => [x, y])), []);使用样例
xProd([1, 2], ['a', 'b']); // [[1, 'a'], [1, 'b'], [2, 'a'], [2, 'b']]