Create 1034-coloring-a-border.js

Author: everthis

1034-coloring-a-border.js

@@ -0,0 +1,49 @@
+/**
+ * @param {number[][]} grid
+ * @param {number} r0
+ * @param {number} c0
+ * @param {number} color
+ * @return {number[][]}
+ */
+const colorBorder = function(grid, r0, c0, color) {
+  const dirs = [[-1,0], [1,0], [0,1], [0,-1]]
+  const c = grid[r0][c0]
+  const rows = grid.length
+  const cols = grid[0].length
+  const visited = Array.from({length: rows}, () => new Array(cols).fill(0))
+  dfs(r0, c0, c, rows, cols, visited, grid, dirs)
+  for(let i = 0; i < rows; i++) {
+    for(let j = 0; j < cols; j++) {
+      if(visited[i][j] === -1) {
+         if(i === 0 || j === 0 || i === rows - 1 || j === cols - 1) {
+            visited[i][j] = -2
+         } else {
+            for(let dir of dirs) {
+              if(visited[i + dir[0]][j + dir[1]] === 0) {
+                 visited[i][j] = -2
+                 break
+              }
+            }    
+         }
+      }
+    }
+  }
+  for(let i = 0; i < rows; i++) {
+    for(let j = 0; j < cols; j++) {
+      if(visited[i][j] === -2) grid[i][j] = color
+    }
+  }
+  
+  return grid
+};
+
+function dfs(row, col, target, rows, cols, visited, grid, dirs) {
+  if(row >= rows || col >= cols || row < 0 || col < 0 || grid[row][col] !== target || visited[row][col] === -1) {
+    return   
+  }
+  visited[row][col] = -1
+  for(let dir of dirs) {
+    dfs(row + dir[0], col+dir[1], target, rows, cols, visited, grid, dirs)
+  }
+  
+}