go 广度搜索案例（迷宫）

 package main

 import (
     "fmt"
     "os"
 )

 /*
 *将文档结构读入到切片中（二维数组）
 *row, col   行数  列数  （文档第一行数据）
 *fmt.Fscanf  逐一字符读取 （遇到换行返回值为0）***Fscan（遇到换行视为空白）***
 *
  */
 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
 }

 //定义点位
 type point struct {
     i, j int
 }

 //运算的坐标点左、下、右、上
 var dirs = [4]point{{-1, 0}, {0, -1}, {1, 0}, {0, 1}}

 //运算
 func (p point) add(r point) point {
     return point{p.i + r.i, p.j + r.j}
 }

 //检查坐标点是否超出范围
 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
 }

 /**
  *行走实现路线
  *1、新建切片数组  记录总行和列数   填充步数
  *
  *
  *
 **/
 func walk(maze [][]int, start, end point) [][]int {
     steps := make([][]int, len(maze)) // slice
     for i := range steps {
         steps[i] = make([]int, len(maze[i]))
     }

     Q := []point{start}

     for len(Q) > 0 {
         cur := Q[0] //队列  多数组 依次
         Q = Q[1:]

         if cur == end {
             break
         }
         //排除走过的不能走的
         for _, dir := range dirs {
             next := cur.add(dir)

             val, ok := next.at(maze)
             if !ok || val == 1 {
                 continue
             }

             val, ok = next.at(steps)
             if !ok || val != 0 {
                 continue
             }

             if next == start {
                 continue
             }

             curSteps, _ := cur.at(steps)
             steps[next.i][next.j] = curSteps + 1

             Q = append(Q, next)
         }
     }

     return steps
 }

 func main() {

     maze := readMaze("maze.in")

     steps := walk(maze, point{0, 0}, point{len(maze) - 1, len(maze[0]) - 1})

     for _, row := range steps {
         for _, val := range row {
             fmt.Printf("%3d", val)
         }
         fmt.Println()
     }

     // TODO: construct path from steps
 }

maze.in

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