/**
 * Created with JetBrains WebStorm.
 * User: leafpanye
 * Date: 2017/12/26.
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 */

//数组合并
//合并数组 arr1 和数组 arr2。不要直接修改数组 arr，结果返回新的数组
//[1, 2, 3, 4], ['a', 'b', 'c', 1]
//[1, 2, 3, 4, 'a', 'b', 'c', 1]

function concat(arr1, arr2) {
    var newArr = [];
    for (var i = 0; i < arr1.length; i++) {
        newArr.push(arr1[i]);
    }
    for (var i = 0; i < arr2.length; i++) {
        newArr.push(arr2[i]);
    }
    return newArr;
}

var a = concat([1, 2, 3, 4], ['a', 'b', 'c', 1]);
console.log(a);