关于javascript:数组相关实现

二维数组的排列组合

给一个数组相似[["0","1"],["a","b"],["m","n"]],失去后果["0am","0an","0bm","0bn","1am","1an","1bm","1bn"]

// 给一个数组相似[["0","1"],["a","b"],["m","n"]],失去后果["0am","0an","0bm","0bn","1am","1an","1bm","1bn"]function getArrayByArrays(array) {  var result = [""];  for (var i = 0; i < array.length; i++) {    result = getValuesByArray(result, array[i]);  }  return result;}function getValuesByArray(result, inArr) {  var arr = [];  for (var i = 0; i < result.length; i++) {    var v1 = result[i];    for (var j = 0; j < inArr.length; j++) {      var v2 = inArr[j];      var value = v1 + v2;      arr.push(value);    }  }  return arr;}let array = [  ["0", "1", "2"],  ["a", "b"],  ["m", "n", "k", "p"],];console.log(getArrayByArrays(array));// ["0am", "0an", "0ak", "0ap", "0bm", "0bn", "0bk", "0bp", "1am", "1an", "1ak", "1ap", "1bm", "1bn", "1bk", "1bp", "2am", "2an", "2ak", "2ap", "2bm", "2bn", "2bk", "2bp"]

reduce实现map

var arr = [1, 2, 3];// map， 返回数组var arr1 = arr.map((item) => item * 2);console.log(arr1) // [2, 4, 6]// reduce， 返回数组var arr2 = arr.reduce((acc, cur) => {  acc.push(cur * 2);  return acc;}, []);console.log(arr2); // [2, 4, 6];