迷宫原型
先创建一个文件,写入迷宫原型的坐标
maze.in
写入下面内容
6 5
0 1 0 0 0
0 0 0 1 0
0 1 0 1 0
1 1 1 0 0
0 1 0 0 1
0 1 0 0 0
实现
maze.go
package main
import (
"fmt"
"os"
)
// 将 maze.in 中的文件内容读取,保存到 maze 二维数组中
// 实现的数据结构: [[0 1 0 0 0] [0 0 0 1 0] [0 1 0 1 0] [1 1 1 0 0] [0 1 0 0 1] [0 1 0 0 0]]
func readMaze(filename string) [][]int {
file, err := os.Open(filename)
if err != nil {
panic(err)
}
var row, col int
fmt.Fscanf(file, "%d %d", &row, &col)
maze := make([][]int, row)
for i := range maze {
maze[i] = make([]int, col)
for j := range maze[i] {
fmt.Fscanf(file, "%d", &maze[i][j])
}
}
return maze
}
type point struct {
i, j int
}
var dirs = [4]point{{-1, 0}, {0, -1}, {1, 0}, {0, 1}}
func (p point) add(r point) point {
return point{p.i + r.i, p.j + r.j}
}
func (p point) at(grid [][]int) (int, bool) {
if p.i < 0 || p.i >= len(grid) {
return 0, false
}
if p.j < 0 || p.j >= len(grid[p.i]) {
return 0, false
}
return grid[p.i][p.j], true
}
func walk(maze [][]int, start, end point) [][]int {
steps := make([][]int, len(maze))
for i := range maze {
steps[i] = make([]int, len(maze[i]))
}
Q := []point{start}
for len(Q) > 0 {
cur := Q[0]
Q = Q[1:]
// 如果发现终点,退出探索
if cur == end {
break
}
for _, dir := range dirs {
next := cur.add(dir)
// 判断是否是不允许走的节点(maze.in 中的 1),如果是跳过去看下一个节点
val, ok := next.at(maze)
if !ok || val == 1 {
continue
}
// 判断是否走过,如果是已经走过的节点不允许再走
val, ok = next.at(steps)
if !ok || val != 0 {
continue
}
// 如果是起点,不允许再走
if next == start {
continue
}
curSteps, _ := cur.at(steps)
steps[next.i][next.j] = curSteps + 1
Q = append(Q, next)
}
}
return steps
}
func printPath(maze [][]int) {
for _, row := range maze {
for _, val := range row {
fmt.Printf("%3d", val)
}
fmt.Println()
}
}
func printStepNum(s [][]int, end point) {
fmt.Printf("到达终点(%d, %d)的总步数是: %d", end.i, end.j, s[end.i][end.j])
}
func main() {
// 获取文件中的地图原型坐标
maze := readMaze("maze/maze.in")
fmt.Println("迷宫原型:")
printPath(maze)
fmt.Println("--------------------------")
fmt.Println("走迷宫的结果:")
end := point{len(maze) - 1, len(maze[0]) - 1}
// 探索迷宫
steps := walk(maze, point{0, 0}, end)
// 打印行走路径
printPath(steps)
fmt.Println("--------------------------")
// 打印到达终点需要的步数
printStepNum(steps, end)
}
结果
迷宫原型:
0 1 0 0 0
0 0 0 1 0
0 1 0 1 0
1 1 1 0 0
0 1 0 0 1
0 1 0 0 0
--------------------------
走迷宫的结果:
0 0 4 5 6
1 2 3 0 7
2 0 4 0 8
0 0 0 10 9
0 0 12 11 0
0 0 13 12 13
--------------------------
到达终点(5, 4)的总步数是: 13