feat: add js solution to lc problem: No.1640. Check Array Formation Through Concatenation (doocs#385)

Author: zhaocchen

solution/1600-1699/1640.Check Array Formation Through Concatenation/README.md

@@ -118,6 +118,33 @@ class Solution {
 }
 ```
 
+### **JavaScript**
+
+```js
+/**
+ * @param {number[]} arr
+ * @param {number[][]} pieces
+ * @return {boolean}
+ */
+var canFormArray = function(arr, pieces) {
+    let mapper = new Map();
+    for (let i = 0; i < pieces.length; i++) {
+        mapper.set(pieces[i][0], pieces[i]);
+    }
+    let i = 0, n = arr.length;
+    while (i < n) {
+        let cur = arr[i];
+        let nums = mapper.get(cur);
+        if (nums == undefined) return false;
+        for (let num of nums) {
+            if (arr[i] != num) return false;
+            i++;
+        }
+    }
+    return true;
+};
+```
+
 ### **...**
 
 ```

solution/1600-1699/1640.Check Array Formation Through Concatenation/README_EN.md

@@ -107,6 +107,33 @@ class Solution {
 }
 ```
 
+### **JavaScript**
+
+```js
+/**
+ * @param {number[]} arr
+ * @param {number[][]} pieces
+ * @return {boolean}
+ */
+var canFormArray = function(arr, pieces) {
+    let mapper = new Map();
+    for (let i = 0; i < pieces.length; i++) {
+        mapper.set(pieces[i][0], pieces[i]);
+    }
+    let i = 0, n = arr.length;
+    while (i < n) {
+        let cur = arr[i];
+        let nums = mapper.get(cur);
+        if (nums == undefined) return false;
+        for (let num of nums) {
+            if (arr[i] != num) return false;
+            i++;
+        }
+    }
+    return true;
+};
+```
+
 ### **...**
 
 ```

solution/1600-1699/1640.Check Array Formation Through Concatenation/Solution.js

@@ -0,0 +1,22 @@
+/**
+ * @param {number[]} arr
+ * @param {number[][]} pieces
+ * @return {boolean}
+ */
+ var canFormArray = function(arr, pieces) {
+    let mapper = new Map();
+    for (let i = 0; i < pieces.length; i++) {
+        mapper.set(pieces[i][0], pieces[i]);
+    }
+    let i = 0, n = arr.length;
+    while (i < n) {
+        let cur = arr[i];
+        let nums = mapper.get(cur);
+        if (nums == undefined) return false;
+        for (let num of nums) {
+            if (arr[i] != num) return false;
+            i++;
+        }
+    }
+    return true;
+};