feat: pascals-triangle

Author: junbinding

arr.pascals-triangle.py

@@ -0,0 +1,36 @@
+from typing import List
+
+
+class Solution:
+    """
+    118. 杨辉三角
+    https://leetcode-cn.com/problems/pascals-triangle/
+    给定一个非负整数 numRows，生成杨辉三角的前 numRows 行。
+    """
+    def generate(self, numRows: int) -> List[List[int]]:
+        res = []
+        i = 0
+        while i < numRows:
+            if i == 0:
+                res.append([1])
+                i += 1
+                continue
+
+            tmp = []
+            j = 0
+            while j <= i:
+                if j >= len(res[i - 1]) or j == 0:
+                    tmp.append(1)
+                else:
+                    tmp.append(res[i - 1][j] + res[i - 1][j - 1])
+
+                j += 1
+
+            res.append(tmp)
+            i += 1
+
+        return res
+
+
+so = Solution()
+print(so.generate(5))