solved set-matrix-zeros, tried longest-substring-...

Author: sangbeenmoon

longest-substring-without-repeating-characters/sangbeenmoon.py

@@ -0,0 +1,16 @@
+class Solution:
+    def lengthOfLongestSubstring(self, s: str) -> int:
+        
+        start = 0
+        last_seen = {}
+        answer = 0
+
+        for i,ch in enumerate(s):
+            if ch in last_seen:
+                if start < last_seen[ch]:
+                    start = last_seen[ch] + 1
+
+            last_seen[ch] = i
+            answer = max(answer, i - start + 1)
+            
+        return answer

set-matrix-zeroes/sangbeenmoon.py

@@ -0,0 +1,22 @@
+# SC : O(m+n)
+
+class Solution:
+    def setZeroes(self, matrix: List[List[int]]) -> None:
+        """
+        Do not return anything, modify matrix in-place instead.
+        """
+        m,n = len(matrix), len(matrix[0])
+        
+        row_dict = {}
+        col_dict = {}
+
+        for r in range(m):
+            for c in range(n):
+                if matrix[r][c] == 0:
+                    row_dict[r] = True
+                    col_dict[c] = True
+
+        for r in range(m):
+            for c in range(n):
+                if r in row_dict or c in col_dict:
+                    matrix[r][c] = 0