[Leo] 14th Week solutions

set-matrix-zeroes/Leo.py

@@ -0,0 +1,25 @@
+class Solution:
+    def setZeroes(self, matrix: List[List[int]]) -> None:
+        """
+        Do not return anything, modify matrix in-place instead.
+        """
+        if not matrix:
+            return []
+
+        m = len(matrix)
+        n = len(matrix[0])
+
+        zeroes_row = [False] * m
+        zeroes_col = [False] * n
+        for row in range(m):
+             for col in range(n):
+                if matrix[row][col] == 0:
+                    zeroes_row[row] = True
+                    zeroes_col[col] = True
+
+        for row in range(m):
+             for col in range(n):
+                if zeroes_row[row] or zeroes_col[col]:
+                     matrix[row][col] = 0
+
+        ## TC: O(mn), SC: O(m+n)

spiral-matrix/Leo.py

@@ -0,0 +1,34 @@
+class Solution:
+    def spiralOrder(self, matrix: List[List[int]]) -> List[int]:
+        res = []
+        while matrix:
+            res.extend(matrix.pop(0))
+            matrix = [*zip(*matrix)][::-1]
+        return res
+
+        ## TC: O(m * n), SC: O(m * n)
+        ## This sloution is kinda tricky and has higher SC than the below one
+
+        # res = []
+        # if len(matrix) == 0:
+        #     return res
+        # row_begin = 0
+        # col_begin = 0
+        # row_end = len(matrix)-1
+        # col_end = len(matrix[0])-1
+        # while (row_begin <= row_end and col_begin <= col_end):
+        #     for i in range(col_begin,col_end+1):
+        #         res.append(matrix[row_begin][i])
+        #     row_begin += 1
+        #     for i in range(row_begin,row_end+1):
+        #         res.append(matrix[i][col_end])
+        #     col_end -= 1
+        #     if (row_begin <= row_end):
+        #         for i in range(col_end,col_begin-1,-1):
+        #             res.append(matrix[row_end][i])
+        #         row_end -= 1
+        #     if (col_begin <= col_end):
+        #         for i in range(row_end,row_begin-1,-1):
+        #             res.append(matrix[i][col_begin])
+        #         col_begin += 1
+        # return res

sum-of-two-integers/Leo.py

@@ -0,0 +1,6 @@
+class Solution:
+    def getSum(self, a: int, b: int) -> int:
+        return add(a,b)
+
+        ## I love this solution :P
+        ## TC: O(1), SC: O(1)