add sol

leetcode/leetcode75/Graphs-BFS/1926.NearestExitFromEntranceInMaze/nearestExitFromEntranceInMaze.go

@@ -0,0 +1,38 @@
+// https://leetcode.com/problems/nearest-exit-from-entrance-in-maze
+
+package main
+
+import "fmt"
+
+func nearestExit(maze [][]byte, entrance []int) int {
+	m, n := len(maze), len(maze[0])
+	q := [][]int{entrance}
+	maze[entrance[0]][entrance[1]] = '+'
+	ans := 0
+	dirs := []int{-1, 0, 1, 0, -1}
+	for len(q) > 0 {
+		ans++
+		for k := len(q); k > 0; k-- {
+			p := q[0]
+			q = q[1:]
+			for l := 0; l < 4; l++ {
+				x, y := p[0]+dirs[l], p[1]+dirs[l+1]
+				if x >= 0 && x < m && y >= 0 && y < n && maze[x][y] == '.' {
+					if x == 0 || x == m-1 || y == 0 || y == n-1 {
+						return ans
+					}
+					q = append(q, []int{x, y})
+					maze[x][y] = '+'
+				}
+			}
+		}
+	}
+	return -1
+}
+
+func main() {
+	maze := [][]byte{{'+', '+', '.', '+'}, {'.', '.', '.', '+'}, {'+', '+', '+', '.'}}
+	entrance := []int{1, 2}
+
+	fmt.Println(nearestExit(maze, entrance))
+}

leetcode/leetcode75/Graphs-BFS/994.RottingOranges/rottingOranges.go

@@ -0,0 +1,49 @@
+// https://leetcode.com/problems/rotting-oranges
+
+package main
+
+import (
+	"fmt"
+)
+
+func orangesRotting(grid [][]int) int {
+	m, n := len(grid), len(grid[0])
+	cnt := 0
+	var q [][]int
+	for i := 0; i < m; i++ {
+		for j := 0; j < n; j++ {
+			if grid[i][j] == 2 {
+				q = append(q, []int{i, j})
+			} else if grid[i][j] == 1 {
+				cnt++
+			}
+		}
+	}
+	ans := 0
+	dirs := []int{-1, 0, 1, 0, -1}
+	for len(q) > 0 && cnt > 0 {
+		ans++
+		for i := len(q); i > 0; i-- {
+			p := q[0]
+			q = q[1:]
+			for j := 0; j < 4; j++ {
+				x, y := p[0]+dirs[j], p[1]+dirs[j+1]
+				if x >= 0 && x < m && y >= 0 && y < n && grid[x][y] == 1 {
+					cnt--
+					grid[x][y] = 2
+					q = append(q, []int{x, y})
+				}
+			}
+		}
+	}
+	if cnt > 0 {
+		return -1
+	}
+	return ans
+}
+
+func main() {
+	grid := [][]int{{2, 1, 1}, {1, 1, 0}, {0, 1, 1}}
+
+	fmt.Println(orangesRotting(grid))
+}