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就是往回一直走，知道我們找到起點位置，在往回走的同時，把每一個經過的格子的背景改爲另外一個背景顏色，這樣就可以在我們的地圖上畫出一個路徑了！","attrs":{}}]}],"attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"好思路清晰，我們來上一波代碼吧！","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"javascript"},"content":[{"type":"text","text":"// 上一部分的代碼，這裏就忽略了...\n// 只要在上部分的代碼後面改造這部分即可\n\n/**\n * 尋路方法 (異步)\n * @param {Array} map 地圖數據\n * @param {Array} start 起點 例如：[0, 0]\n * @param {Array} end 終點 例如：[50, 50]\n * @return Boolean\n */\nfunction sleep(t) {\n return new Promise(function (resolve) {\n setTimeout(resolve, t);\n });\n}\n\n/**\n * 入隊方法 (異步)\n * @param {Integer} x\n * @param {Integer} y\n */\nasync function findPath(map, start, end) {\n // 創建一個記錄表格\n let table = Object.create(map);\n let queue = [start];\n\n /**\n * 入隊方法 (異步)\n * @param {Integer} x\n * @param {Integer} y\n * @param {Array} pre 上一個格子的座標：[x,y]\n */\n async function insert(x, y, pre) {\n // 到達底盤邊緣，直接停止\n if (x < 0 || x >= 100 || y < 0 || y >= 100) return;\n // 遇到地圖的牆，也停止\n if (table[y * 100 + x]) return;\n // 加入 30 毫秒的停頓，讓我們可以看到 UI 上面的變化\n // await sleep(1);\n // 給搜索到的路徑的格子加上背景顏色\n container.children[y * 100 + x].style.backgroundColor = 'DARKSLATEBLUE';\n // 標記走過的格子的值，標記爲上一個格子的 x，y 位置\n table[y * 100 + x] = pre;\n // 把可走的路推入隊列\n queue.push([x, y]);\n }\n\n // 循環格子 4 邊的格子\n while (queue.length) {\n let [x, y] = queue.shift();\n // console.log(x, y);\n\n // 遇到了終點位置就可以返回了\n if (x === end[0] && y === end[1]) {\n let path = [];\n\n // 往回走，直到走到起點\n // 這樣就能畫出最佳路徑了\n while (x != start[0] || y != start[1]) {\n path.push(map[y * 100 + x]);\n [x, y] = table[y * 100 + x];\n await sleep(1);\n container.children[y * 100 + x].style.backgroundColor = 'fuchsia';\n }\n\n return path;\n }\n\n // 把上下左右推入隊列\n await insert(x - 1, y, [x, y]);\n await insert(x, y - 1, [x, y]);\n await insert(x + 1, y, [x, y]);\n await insert(x, y + 1, [x, y]);\n\n // 把 4 個 斜邊推入隊列\n await insert(x - 1, y - 1, [x, y]);\n await insert(x + 1, y - 1, [x, y]);\n await insert(x - 1, y + 1, [x, y]);\n await insert(x + 1, y + 1, [x, y]);\n }\n\n return null;\n}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"注意：這裏我們把原來的 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"path","attrs":{}}],"attrs":{}},{"type":"text","text":" 函數名改爲了 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"findPath","attrs":{}}],"attrs":{}},{"type":"text","text":"，因爲在尋找路徑的 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"while","attrs":{}}],"attrs":{}},{"type":"text","text":" 循環裏面我們用了 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"path","attrs":{}}],"attrs":{}},{"type":"text","text":" 做爲記錄路徑的變量。這裏還需要注意的就是，我們的 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"find","attrs":{}}],"attrs":{}},{"type":"text","text":" 按鈕裏面的函數調用也需要一併修改哦。","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"\n\n \n \n
","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":" 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","attrs":{}},{"type":"link","attrs":{"href":"https://github.com/TriDiamond/frontend-tutorials/blob/master/exercises/path-finder/4-map-find-path.html","title":""},"content":[{"type":"text","text":"查看代碼","attrs":{}}]},{"type":"text","text":" ｜ ","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"喜歡的同學 🌟star 一下謝謝！","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":1},"content":[{"type":"text","text":"啓發式尋路（A*）","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"到這裏我們已經完成了整個廣度優先尋路的算法。但是廣搜式尋路是不是最好的尋路方案呢？","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"其實並不是的","attrs":{}}],"attrs":{}},{"type":"text","text":"!","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/bc/bc8b68ef9eb75f70203c94c48089c90b.gif","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"通過各位數學科學家的努力下，他們證明了一件事情。我們是可以有一種方法能夠加速尋路的，通過用這個方法我們不需要使用一個非常傻的方式來挨個去找。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"這種尋路的方式叫做 “","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"啓發式尋路","attrs":{}}],"attrs":{}},{"type":"text","text":"”","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"啓發式尋路就是用一個函數去判斷這些點擴展的優先級。只要我們判斷好了優先級，我們就可以有目的的去驗者格子的方向做優先找路。","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"“但是這個找到的路徑是不是最佳路徑呀？說的那麼神奇的。“ 說實話，這個我們普通人的思路就排不上用場了。但是數學家證明了一件事情，只要我們使用啓發式函數來估計值，並且這些值能夠一定小於當前點到終點的路徑的長度，這樣就一定能找到最優路徑。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"這種能找到最優路徑的啓發式尋路，在計算機裏面我們叫它做 “","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"A*","attrs":{}}],"attrs":{}},{"type":"text","text":"”。這裏面的 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"A","attrs":{}}],"attrs":{}},{"type":"text","text":" 代表着一種不一定能找到最優路徑的啓發式尋路。所以 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"A*","attrs":{}}],"attrs":{}},{"type":"text","text":" 就是 A 尋路的一個特例，是一種可以找到最佳路徑的一種算法。","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"要實現這個啓發式尋路，其實我們是不需要改過多我們 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"findPath()","attrs":{}}],"attrs":{}},{"type":"text","text":"函數裏面的代碼的。我們要改的是我們存儲的數據結構，也就是我們的 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"queue","attrs":{}}],"attrs":{}},{"type":"text","text":" 隊列。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"我們要把 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"queue","attrs":{}}],"attrs":{}},{"type":"text","text":" 的先進先出變成一個","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"優先隊列 (Prioritized 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隊列裏面的數據","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":2,"align":null,"origin":null},"content":[{"type":"text","text":"可以支持傳入排序函數（也就是和我們 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"array sort","attrs":{}}],"attrs":{}},{"type":"text","text":" 函數一樣的功能，可以傳入一個排序規則函數，也叫 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"compare","attrs":{}}],"attrs":{}},{"type":"text","text":" 函數）","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":3,"align":null,"origin":null},"content":[{"type":"text","text":"在我們通過這個類獲取值的時候給我們數據裏面的最小值","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":4,"align":null,"origin":null},"content":[{"type":"text","text":"在我們插入數據的時候不需要排序，只是單純的保存","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":5,"align":null,"origin":null},"content":[{"type":"text","text":"每次去除數據的時候，可以把輸出的數據在類的數據裏面刪除掉","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":6,"align":null,"origin":null},"content":[{"type":"text","text":"這樣我們就可以一直在裏面獲取數據，知道沒有數據爲止","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":7,"align":null,"origin":null},"content":[{"type":"text","text":"最後加入一個可以獲取當前數據的長度（這個在我們的尋路算法中需要用到）","attrs":{}}]}],"attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"這裏我們用一個非常 “土鱉” 的數組來實現這個 Sorted 類，但是在計算機當中，我們還有很多其他方式可以實現這一種類。比如說 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"winner tree","attrs":{}}],"attrs":{}},{"type":"text","text":"，","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"堆 (heap)","attrs":{}}],"attrs":{}},{"type":"text","text":"，","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"排序二叉樹","attrs":{}}],"attrs":{}},{"type":"text","text":" 等很多的不同思路來實現有序的數據結構。","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"好廢話少說，我們來看看怎麼實現這個數據結構：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"javascript"},"content":[{"type":"text","text":"/** 排序數據類 */\nclass Sorted {\n constructor(data, compare) {\n this.data = data.slice();\n this.compare = compare || ((a, b) => a - b);\n }\n take() {\n // 考慮到 null 也是可以參與比較的，所以這裏返回 null 是不合適的\n if (!this.data.length) return;\n // 記錄最小的值\n // 默認第一個位置爲最小值\n let min = this.data[0];\n // 記錄最小值的位置\n let minIndex = 0;\n\n // 開始比較數組裏面的所有值，找到更小的值，就記錄爲 min\n // 同時記錄最小值，和最小值的位置\n for (let i = 1; i < this.data.length; i++) {\n if (this.compare(this.data[i], min) < 0) {\n min = this.data[i];\n minIndex = i;\n }\n }\n\n // 現在我們要把最小值拿出去了，所以要在我們當前的數據中移除\n // 這裏我們不考慮使用 splice，因爲 splice 移除會涉及數組內的元素都要往前挪動\n // 這樣 splice 就會有一個 O(N) 的時間複雜度\n // 這裏我們用一個小技巧，把數組裏面最後一位的值挪動到當前發現最小值的位置\n // 最後使用 pop 把最後一位數據移除\n this.data[minIndex] = this.data[this.data.length - 1];\n this.data.pop();\n // 最後把最小值輸出\n return min;\n }\n give(value) {\n this.data.push(value);\n }\n get length() {\n return this.data.length;\n }\n}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"有了這個 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"Sorted","attrs":{}}],"attrs":{}},{"type":"text","text":" 的數據結構之後，我們就可以用來解決我們的尋路問題，讓我們可以找到最佳的路徑了。","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"加入這個最佳路徑的邏輯，我們需要改到一下幾個點：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"numberedlist","attrs":{"start":"1","normalizeStart":1},"content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":1,"align":null,"origin":null},"content":[{"type":"text","text":"首先改寫我們的存儲數據的 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"queue","attrs":{}}],"attrs":{}},{"type":"text","text":"，使用我們 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"Sorted","attrs":{}}],"attrs":{}},{"type":"text","text":" 的排序數據結構","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":2,"align":null,"origin":null},"content":[{"type":"text","text":"編寫一個 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"distance()","attrs":{}}],"attrs":{}},{"type":"text","text":" 函數來運算任何一個格子與終點格子的直線距離","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":3,"align":null,"origin":null},"content":[{"type":"text","text":"把所有入隊列和出隊列的調用改爲使用 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"Sorted","attrs":{}}],"attrs":{}},{"type":"text","text":" 類裏面的 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"take","attrs":{}}],"attrs":{}},{"type":"text","text":" 取值 和 ","attrs":{}},{"type":"codeinline","content":[{"type":"text","text":"give","attrs":{}}],"attrs":{}},{"type":"text","text":" 插入值函數","attrs":{}}]}],"attrs":{}},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":4,"align":null,"origin":null},"content":[{"type":"text","text":"其他地方基本就沒有什麼改變了","attrs":{}}]}],"attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"接下來我們來看看代碼是怎麼實現的：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"codeblock","attrs":{"lang":"javascript"},"content":[{"type":"text","text":"// 上一部分的代碼，這裏就忽略了...\n// 只要在上部分的代碼後面改造這部分即可\n\n/**\n * 尋路方法 (異步)\n * @param {Array} map 地圖數據\n * @param {Array} start 起點 例如：[0, 0]\n * @param {Array} end 終點 例如：[50, 50]\n * @return Boolean\n */\nasync function findPath(map, start, end) {\n // 創建一個記錄表格\n let table = Object.create(map);\n let queue = new Sorted([start], (a, b) => distance(a) - distance(b));\n\n async function insert(x, y, pre) {\n // 到達底盤邊緣，直接停止\n if (x < 0 || x >= 100 || y < 0 || y >= 100) return;\n // 遇到地圖的牆，也停止\n if (table[y * 100 + x]) return;\n // 加入 30 毫秒的停頓，讓我們可以看到 UI 上面的變化\n await sleep(1);\n // 給搜索到的路徑的格子加上背景顏色\n container.children[y * 100 + x].style.backgroundColor = 'DARKSLATEBLUE';\n // 標記走過的格子的值，標記爲上一個格子的 x，y 位置\n table[y * 100 + x] = pre;\n // 把可走的路推入隊列\n queue.give([x, y]);\n }\n\n /**\n * 獲取格與格之前的距離\n * @param {Array} point 當前格子的座標：[x,y]\n */\n function distance(point) {\n // 使用三角形 x^2 + y^2 = z^2 的方式來計算距離\n return (point[0] - end[0]) ** 2 + (point[1] - end[1]) ** 2;\n }\n\n // 循環格子 4 邊的格子\n while (queue.length) {\n let [x, y] = queue.take();\n // console.log(x, y);\n\n // 遇到了終點位置就可以返回了\n if (x === end[0] && y === end[1]) {\n let path = [];\n\n // 往回走，直到走到起點\n // 這樣就能畫出最佳路徑了\n while (x != start[0] || y != start[1]) {\n path.push(map[y * 100 + x]);\n [x, y] = table[y * 100 + x];\n container.children[y * 100 + x].style.backgroundColor = 'fuchsia';\n }\n\n return path;\n }\n\n // 把上下左右推入隊列\n await insert(x - 1, y, [x, y]);\n await insert(x, y - 1, [x, y]);\n await insert(x + 1, y, [x, y]);\n await insert(x, y + 1, [x, y]);\n\n // 把 4 個 斜邊推入隊列\n await insert(x - 1, y - 1, [x, y]);\n await insert(x + 1, y - 1, [x, y]);\n await insert(x - 1, y + 1, [x, y]);\n await insert(x + 1, y + 1, [x, y]);\n }\n\n return null;\n}","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"這個最終的運行效果如下：","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/cd/cd7dfa17b40260f1210e225cfb5b1c5c.png","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"link","attrs":{"href":"http://tridiamond.tech/frontend-tutorials/exercises/path-finder/6-map-best-path.html","title":""},"content":[{"type":"text","text":"查看效果","attrs":{}}]},{"type":"text","text":" ｜ ","attrs":{}},{"type":"link","attrs":{"href":"https://github.com/TriDiamond/frontend-tutorials/blob/master/exercises/path-finder/6-map-best-path.html","title":""},"content":[{"type":"text","text":"查看代碼","attrs":{}}]},{"type":"text","text":" ｜ ","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"喜歡的同學 🌟star 一下謝謝！","attrs":{}}]}],"attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"horizontalrule","attrs":{}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"我是來自《","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"技術銀河","attrs":{}},{"type":"text","text":"》的","attrs":{}},{"type":"text","marks":[{"type":"strong","attrs":{}}],"text":"三鑽","attrs":{}},{"type":"text","text":"：\"學習是爲了成長，成長是爲了不退步。堅持才能成功，失敗只是因爲沒有堅持。同學們加油哦！下期見！\"","attrs":{}}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/f7/f7db8645b6fdfa85351bc5f5aeb79aeb.gif","alt":null,"title":"","style":[{"key":"width","value":"25%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"horizontalrule","attrs":{}},{"type":"heading","attrs":{"align":null,"level":1}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}}]}