Returns the powerset of a given array of numbers.
Use Array.prototype.reduce()
combined with Array.prototype.map()
to iterate over elements and combine into an array containing all combinations.
代码片段
const powerset = arr => arr.reduce((a, v) => a.concat(a.map(r => [v].concat(r))), [[]]);
使用样例
powerset([1, 2]); // [[], [1], [2], [2, 1]]