0695 Max Area Of Island

Author: seankit

swift/0695-max-area-of-island.swift

@@ -0,0 +1,35 @@
+class Solution {
+    func maxAreaOfIsland(_ grid: [[Int]]) -> Int {
+        let numRows = grid.count
+        let numColumns = grid[0].count
+        
+        var grid = grid
+        var maxArea = 0
+        
+        for row in 0..<numRows {
+            for column in 0..<numColumns {
+                guard grid[row][column] == 1 else { continue }
+                
+                let area = dfs(row: row, column: column, grid: &grid)
+                maxArea = max(maxArea, area)
+            }
+        }
+        return maxArea
+    }
+    
+    private func dfs(row: Int, column: Int, grid: inout [[Int]]) -> Int {
+        guard row >= 0,
+              row < grid.count,
+              column >= 0,
+              column < grid[0].count,
+              grid[row][column] == 1
+        else { return 0 }
+        
+        grid[row][column] = 0
+        
+        return 1 + dfs(row: row + 1, column: column, grid: &grid)
+                 + dfs(row: row - 1, column: column, grid: &grid)
+                 + dfs(row: row, column: column + 1, grid: &grid)
+                 + dfs(row: row, column: column - 1, grid: &grid)
+    }
+}