嵌套列表到陣列

Question

我正在努力與這個kata，指示我從嵌套列表中創建一個數組。我可以找到解釋如何使用Java來做到這一點，但這對我仍然有點困惑。

這是我這麼遠......

function listToArray(list) { 
 
    var listArray = []; 
 
    for (var i = 0; i < list.length; i++) { 
 
    listArray[i] = list.value(i); 
 
    }; 
 
    return listArray; 
 
};

測試用例...

var list1 = {value: 1, next: {value: 2, next: {value: 3, next: null}}}; 
 
var list2 = {value: "foo", next: {value: "bar", next: null}}; 
 

 
Test.assertSimilar(listToArray(list1), [1, 2, 3]); 
 
Test.assertSimilar(listToArray(list2), ["foo", "bar"]);

感謝幫助！

Answer 1

這是一個簡單的鏈表指針追逐：

function listToArray(list) { 
    var listArray = []; 
    while (list !== null) { 
    listArray.push(list.value); 
    list = list.next; 
    } 
    return listArray; 
}; 

Answer 2

遞歸就做

function listToArray(list) { 
 
    var res = []; 
 
    Object.keys(list).forEach(function(k) { 
 
    if (typeof list[k] == 'object' && list[k] !== null) 
 
     [].push.apply(res, listToArray(list[k])); 
 
    else if (list[k] !== null) 
 
     res.push(list[k]); 
 
    }); 
 
    return res; 
 
}; 
 

 
var list1 = { 
 
    value: 1, 
 
    next: { 
 
    value: 2, 
 
    next: { 
 
     value: 3, 
 
     next: null 
 
    } 
 
    } 
 
}; 
 
var list2 = { 
 
    value: "foo", 
 
    next: { 
 
    value: "bar", 
 
    next: null 
 
    } 
 
}; 
 

 
console.log(listToArray(list1)); 
 
console.log(listToArray(list2));

Answer 3

使用遞歸另一種解決方案：

var list1 = {value: 1, next: {value: 2, next: {value: 3, next: null}}}; 
 
var list2 = {value: "foo", next: {value: "bar", next: null}}; 
 

 
function convertToArray(list, result) { 
 
    result.push(list.value); 
 
    list.next && convertToArray(list.next,result); 
 
    return result; 
 
} 
 

 
console.log(convertToArray(list1,[])); 
 
console.log(convertToArray(list2,[]));

Answer 4

你必須直到到達null點深入挖掘的對象。

var list1 = {value: 1, next: {value: 2, next: {value: 3, next: null}}}; 
 
var list2 = {value: "foo", next: {value: "bar", next: null}}; 
 

 
function listToArray(list) { 
 
    var curr = list, arr = []; 
 
    while (curr != null) { 
 
    arr.push(curr.value); 
 
    curr = curr.next; 
 
    } 
 
    return arr; 
 
} 
 

 
console.log(listToArray(list1)); 
 
console.log(listToArray(list2));