添加59.螺旋矩阵IIjavaScript版本

problems/0059.螺旋矩阵II.md

@@ -224,6 +224,49 @@ class Solution:
         return matrix
 ```
 
+javaScript
+
+```js
+
+/**
+ * @param {number} n
+ * @return {number[][]}
+ */
+var generateMatrix = function(n) {
+    // new Array(n).fill(new Array(n))
+    // 使用fill --> 填充的是同一个数组地址
+    const res = Array.from({length: n}).map(() => new Array(n));
+    let loop = n >> 1, i = 0, //循环次数
+        count = 1,
+        startX = startY = 0; // 起始位置 
+    while(++i <= loop) {
+        // 定义行列
+        let row = startX, column = startY;
+        // [ startY, n - i)
+        while(column < n - i) {
+            res[row][column++] = count++;
+        }
+        // [ startX, n - i)
+        while(row < n - i) {
+            res[row++][column] = count++;
+        }
+        // [n - i ,  startY)
+        while(column > startY) {
+            res[row][column--] = count++; 
+        }
+        // [n - i ,  startX)
+        while(row > startX) {
+            res[row--][column] = count++;
+        }
+        startX = ++startY;
+    }
+    if(n & 1) {
+        res[startX][startY] = count;
+    }
+    return res;
+};
+```
+
 
 
 -----------------------