diff --git a/.idea/.gitignore b/.idea/.gitignore
new file mode 100644
index 00000000..13566b81
--- /dev/null
+++ b/.idea/.gitignore
@@ -0,0 +1,8 @@
+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml
diff --git a/.idea/encodings.xml b/.idea/encodings.xml
new file mode 100644
index 00000000..15a15b21
--- /dev/null
+++ b/.idea/encodings.xml
@@ -0,0 +1,4 @@
+
+
+
+
\ No newline at end of file
diff --git a/.idea/inspectionProfiles/profiles_settings.xml b/.idea/inspectionProfiles/profiles_settings.xml
new file mode 100644
index 00000000..105ce2da
--- /dev/null
+++ b/.idea/inspectionProfiles/profiles_settings.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/leetcode-master.iml b/.idea/leetcode-master.iml
new file mode 100644
index 00000000..d0876a78
--- /dev/null
+++ b/.idea/leetcode-master.iml
@@ -0,0 +1,8 @@
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 00000000..4d519243
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,4 @@
+
+
+
+
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
new file mode 100644
index 00000000..7c250acd
--- /dev/null
+++ b/.idea/modules.xml
@@ -0,0 +1,8 @@
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 00000000..35eb1ddf
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
\ No newline at end of file
diff --git a/problems/0054.螺旋矩阵.md b/problems/0054.螺旋矩阵.md
index 44a7749d..85e6a936 100644
--- a/problems/0054.螺旋矩阵.md
+++ b/problems/0054.螺旋矩阵.md
@@ -306,6 +306,47 @@ class Solution(object):
return result
```
+版本二：定义四个边界
+```python
+class Solution(object):
+ def spiralOrder(self, matrix):
+ """
+ :type matrix: List[List[int]]
+ :rtype: List[int]
+ """
+ if not matrix:
+ return []
+
+ rows = len(matrix)
+ cols = len(matrix[0])
+ top, bottom, left, right = 0, rows - 1, 0, cols - 1
+ print_list = []
+
+ while top <= bottom and left <= right:
+ # 从左到右
+ for i in range(left, right + 1):
+ print_list.append(matrix[top][i])
+ top += 1
+
+ # 从上到下
+ for i in range(top, bottom + 1):
+ print_list.append(matrix[i][right])
+ right -= 1
+
+ # 从右到左
+ if top <= bottom:
+ for i in range(right, left - 1, -1):
+ print_list.append(matrix[bottom][i])
+ bottom -= 1
+
+ # 从下到上
+ if left <= right:
+ for i in range(bottom, top - 1, -1):
+ print_list.append(matrix[i][left])
+ left += 1
+
+ return print_list
+```
diff --git a/problems/0059.螺旋矩阵II.md b/problems/0059.螺旋矩阵II.md
index 58378ffc..8823a0d8 100644
--- a/problems/0059.螺旋矩阵II.md
+++ b/problems/0059.螺旋矩阵II.md
@@ -207,6 +207,50 @@ class Solution:
return nums
```
+版本二：定义四个边界
+```python
+class Solution(object):
+ def generateMatrix(self, n):
+ if n <= 0:
+ return []
+
+ # 初始化 n x n 矩阵
+ matrix = [[0]*n for _ in range(n)]
+
+ # 初始化边界和起始值
+ top, bottom, left, right = 0, n-1, 0, n-1
+ num = 1
+
+ while top <= bottom and left <= right:
+ # 从左到右填充上边界
+ for i in range(left, right + 1):
+ matrix[top][i] = num
+ num += 1
+ top += 1
+
+ # 从上到下填充右边界
+ for i in range(top, bottom + 1):
+ matrix[i][right] = num
+ num += 1
+ right -= 1
+
+ # 从右到左填充下边界
+
+ for i in range(right, left - 1, -1):
+ matrix[bottom][i] = num
+ num += 1
+ bottom -= 1
+
+ # 从下到上填充左边界
+
+ for i in range(bottom, top - 1, -1):
+ matrix[i][left] = num
+ num += 1
+ left += 1
+
+ return matrix
+```
+
### JavaScript:
```javascript