Time: 26 ms (56.14%), Space: 80.8 MB (6.02%) - LeetHub

py3-coder · py3-coder · commit 5a6aba1f9331 · 2024-11-21T22:41:24.000+05:30
diff --git a/2257-count-unguarded-cells-in-the-grid/2257-count-unguarded-cells-in-the-grid.java b/2257-count-unguarded-cells-in-the-grid/2257-count-unguarded-cells-in-the-grid.java
@@ -0,0 +1,34 @@
+class Solution {
+    public int countUnguarded(int m, int n, int[][] guards, int[][] walls) {
+        
+        int[][] dirs = {{1,0},{-1,0},{0,1},{0,-1}};
+        char[][] matrix = new char[m][n];
+        int ans = m*n-guards.length-walls.length;
+        
+        for(int[] wall : walls){
+            matrix[wall[0]][wall[1]]='W';
+        }
+        for(int[] guard : guards){
+            matrix[guard[0]][guard[1]]='G';
+        }
+        
+        for(int[] point : guards){
+            for(int[] dir : dirs){
+                int nrow =point[0]+dir[0];
+                int ncol =point[1]+dir[1];
+                
+                while(!(nrow<0 || ncol<0 || nrow>=m || ncol>=n ||
+                        matrix[nrow][ncol]=='G' || matrix[nrow][ncol]=='W')){
+                    
+                    if(matrix[nrow][ncol]!='P'){
+                        ans--;
+                    }
+                    matrix[nrow][ncol]='P';
+                    nrow +=dir[0];
+                    ncol +=dir[1];
+                }
+            }
+        }
+        return ans;
+    }
+}
