js 遞歸查找

https://www.v2ex.com/t/661182

let arr = [
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                "id": 2,
                "label": "技術",
                "value": 2
            },
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                "pid": 1,
                "id": 3,
                "label": "產品",
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            {
                "children": [
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                        "id": 26,
                        "label": "測試欄目 1",
                        "value": 26
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                "label": "項目",
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                "pid": 1,
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                "label": "國際",
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                "pid": 1,
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                "label": "研究",
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                        "label": "活動",
                        "value": 19
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                    {
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                        "id": 20,
                        "label": "新聞",
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                        "id": 21,
                        "label": "資訊",
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                        "id": 22,
                        "label": "新聞",
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                        "pid": 7,
                        "id": 23,
                        "label": "知識",
                        "value": 23
                    },
                    {
                        "children": [
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                                "children": [
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                                        "pid": 11,
                                        "id": 12,
                                        "label": "欄目 4",
                                        "value": 12
                                    }
                                ],
                                "pid": 9,
                                "id": 11,
                                "label": "欄目 3",
                                "value": 11
                            }
                        ],
                        "pid": 7,
                        "id": 9,
                        "label": "幫助中心",
                        "value": 9
                    }
                ],
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                "id": 7,
                "label": "新聞資訊",
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                "children": [
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                        "id": 13,
                        "label": "簡介",
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                        "pid": 8,
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                        "label": "榮譽",
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                        "label": "關懷",
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                        "label": "我們",
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                "label": "我們",
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                "pid": 1,
                "id": 17,
                "label": "公告",
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                "pid": 1,
                "id": 6,
                "label": "展示",
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            }
        ],
        "pid": 0,
        "id": 1,
        "label": "主目錄",
        "value": 1
    }
]

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}

function collect(obj) {
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}