Create as_far_from_land_as_possible.cpp

Author: avidLearnerInProgress

as_far_from_land_as_possible.cpp

@@ -0,0 +1,34 @@
+class Solution {
+public:
+    int maxDistance(vector<vector<int>>& grid) {
+        queue<pair<int,int>> q;
+        int steps = 0,r = grid.size(),c = grid[0].size();
+        
+        for(int i = 0; i < r; i++) {
+            for(int j = 0; j < c; j++) {
+                if(grid[i][j] == 1) {
+                    q.push({i-1, j});
+                    q.push({i+1, j});
+                    q.push({i, j-1});
+                    q.push({i, j+1});
+                }
+            }
+        }
+        while(!q.empty()) {
+            int size = q.size();
+            steps++;
+            for(int k = 0; k < size; k++) {
+                int i = q.front().first, j = q.front().second;
+                q.pop();
+                if(i >= 0 && j >= 0 && i < r && j < c&& grid[i][j] == 0) {
+                    grid[i][j] = steps;
+                    q.push({i-1, j});
+                    q.push({i+1, j});
+                    q.push({i, j-1});
+                    q.push({i, j+1});
+                }
+            }
+        }
+        return steps == 1 ? -1 : steps - 1;
+    }
+};