package main

import(
    "fmt"
    "bufio"
    "os"
)

type PII struct{
    first int
    second int
}

func main(){
    var reader = bufio.NewReader(os.Stdin)
    var n,m int
    fmt.Fscan(reader, &n, &m)
    //fmt.Println(n)
    g := make([][]int, n)
    for i := range g {
        g[i] = make([]int, m)
    }

    for i := 0; i < n; i++{
        for j := 0; j <m; j++{
            fmt.Fscan(reader, &g[i][j])
        }
    }

    dx := [4]int{-1, 0, 1, 0}
    dy := [4]int{0, 1, 0, -1}

    head := 0
    tail := 0
    q := make([]PII, (n+2)*(n+2))
    q[0]= PII{0,0}

    d := make([][]int, n) //distance距离起点距离
    for i := range d{
        d[i] = make([]int, m)
        for j := range d[i]{
            d[i][j] = -1
        }
    }
    d[0][0]=0
    var bfs func(g [][]int) int
    bfs = func(g [][]int) int{
        for head <=tail {
            t := q[head]
            head ++
            for i := 0; i < 4; i++{
                x := t.first + dx[i]
                y := t.second + dy[i]
                if x >=0 && x < n && y >= 0 && y < m && d[x][y] == -1 && g[x][y] == 0{
                    d[x][y] = d[t.first][t.second] + 1
                    tail ++
                    q[tail] = PII{x, y}
                }
            }
        }
        return d[n - 1][m - 1]
    }
    //result := bfs(g)
    fmt.Println(bfs(g))
}