Leetcode accepted

PriyankaKhire · PriyankaKhire · commit a44655f8eae1 · 2021-08-22T00:25:54.000-07:00
diff --git a/Blind 75/Programs/Set Matrix Zeroes.py b/Blind 75/Programs/Set Matrix Zeroes.py
@@ -0,0 +1,36 @@
+# Set Matrix Zeroes
+# https://leetcode.com/problems/set-matrix-zeroes/
+
+class Solution(object):
+    def setRowToX(self, row, matrix):
+        for col in range(len(matrix[0])):
+            if (matrix[row][col] != 0):
+                matrix[row][col] = "x"
+    
+    def setColToX(self, col, matrix):
+        for row in range(len(matrix)):
+            if (matrix[row][col] != 0):
+                matrix[row][col] = "x"
+    
+    def setToZero(self, matrix):
+        for row in range(len(matrix)):
+            for col in range(len(matrix[0])):
+                if (matrix[row][col] == "x"):
+                    matrix[row][col] = 0
+                
+    def setZeroes(self, matrix):
+        # set row and col of the cell that has 0 to x
+        for row in range(len(matrix)):
+            for col in range(len(matrix[0])):
+                if (matrix[row][col] == 0):
+                    self.setRowToX(row, matrix)
+                    self.setColToX(col, matrix)
+                    
+        # set the negative numbers to zero
+        self.setToZero(matrix)
+        
+        """
+        :type matrix: List[List[int]]
+        :rtype: None Do not return anything, modify matrix in-place instead.
+        """
+        
diff --git a/Blind 75/README.md b/Blind 75/README.md
@@ -194,7 +194,12 @@
     </ul>
   <h2>Matrix</h2>
     <ul>
-      <li>Set Matrix Zeroes</li>
+      <li><a href="Programs/Set Matrix Zeroes.py">Set Matrix Zeroes</a> 
+        <p><b>Approach</b>: Set the row and col of the cell with zero to value "x". 
+          Then in second pass, change all the cells with "x" to zero.
+          This ensures we use no extra space and do it in O(n) time.
+        </p>
+      </li>
       <li>Spiral Matrix</li>
       <li>Rotate Image</li>
       <li>Word Search</li>
