Go: package main

import (
	"bufio"
	"container/list"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	io := NewIo()
	defer io.Flush()
	for {
		w, h := io.NextInt(), io.NextInt()
		if w == 0 {
			break
		}
		xWall := make([][]int, h)
		yWall := make([][]int, h)
		for i := 0; i < h; i++ {
			xWall[i], yWall[i] = make([]int, w), make([]int, w)
			for j := 0; j < w; j++ {
				xWall[i][j], yWall[i][j] = -1, -1
			}
		}
		for i := 0; i < h*2-1; i++ {
			if i%2 == 0 {
				for j := 0; j < w-1; j++ {
					xWall[i/2][j] = io.NextInt()
				}
			} else {
				for j := 0; j < w; j++ {
					yWall[i/2][j] = io.NextInt()
				}
			}
		}
		//io.Println(bfs(w, h, xWall, yWall))
		fmt.Println(bfs(w, h, xWall, yWall))
	}
}

type P struct {
	x, y int
}

func bfs(w, h int, x, y [][]int) int {
	d := make([][]int, h)
	for i := 0; i < h; i++ {
		d[i] = make([]int, w)
	}
	q := list.New()
	q.PushBack(P{0, 0})
	d[0][0] = 1

	for q.Len() != 0 {
		pos := q.Remove(q.Front()).(P)
		if pos.x == w-1 && pos.y == h-1 {
			break
		}
		if pos.x > 0 && x[pos.y][pos.x-1] == 0 && d[pos.y][pos.x-1] == 0 {
			d[pos.y][pos.x-1] = d[pos.y][pos.x] + 1
			q.PushBack(P{pos.x - 1, pos.y})
		}
		if pos.x < w-1 && x[pos.y][pos.x] == 0 && d[pos.y][pos.x+1] == 0 {
			d[pos.y][pos.x+1] = d[pos.y][pos.x] + 1
			q.PushBack(P{pos.x + 1, pos.y})
		}
		if pos.y > 0 && y[pos.y-1][pos.x] == 0 && d[pos.y-1][pos.x] == 0 {
			d[pos.y-1][pos.x] = d[pos.y][pos.x] + 1
			q.PushBack(P{pos.x, pos.y - 1})
		}
		if pos.y < h-1 && y[pos.y][pos.x] == 0 && d[pos.y+1][pos.x] == 0 {
			d[pos.y+1][pos.x] = d[pos.y][pos.x] + 1
			q.PushBack(P{pos.x, pos.y + 1})
		}
	}
	return d[h-1][w-1]
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

C++: #include <iostream>
#include <queue>
using namespace std;
 
typedef pair<int,int> P;
 
int d[31][31];
int dx[4]={1,0,-1,0},dy[4]={0,1,0,-1};
enum{RIGHT,UP,LEFT,DOWN};
 
bool tate[30+1][30];
bool yoko[30][30+1];
int W,H;
 
bool canmove(int x,int y,int mx,int my,int d){
     if(mx<0||my<0||mx>=W||my>=H){
      return false;
     }else{
      switch(d){
      case RIGHT:
           if(tate[x][y])return false;
           break;
      case LEFT:
           if(tate[x-1][y])return false;
           break;
      case DOWN:
           if(yoko[x][y-1])return false;
           break;
      case UP:
           if(yoko[x][y])return false;
      }
      return true;
     }
}
 
int bfs(){
  queue< pair<int,int> > que;
 
  for(int i=0;i<W;i++){
    for(int j=0;j<H;j++){
      d[i][j]=-1;
    }
  }
 
  que.push(P(0,0));
  d[0][0]=0;
 
  while(que.size()){
    P p=que.front();
    que.pop();
    if(p.first==W-1&&p.second==H-1)break;
    for(int i=0;i<4;i++){
      int nx=p.first+dx[i],ny=p.second+dy[i];
      if(canmove(p.first,p.second,nx,ny,i)&&d[nx][ny]==-1){
    que.push(P(nx,ny));
    d[nx][ny]=d[p.first][p.second]+1;
      }
    }
  }
  return d[W-1][H-1];
}
       
int main(){
     for(int i=0;i<30;i++){
      for(int j=0;j<31;j++){
           tate[j][i]=0;
           yoko[i][j]=0;
      }
     }
     while(cin>>W>>H,W||H){
      for(int i=0;i<H;i++){
           for(int j=0;j<W-1;j++){
            cin>>tate[j][i];
           }
           if(i!=H-1){
            for(int j=0;j<W;j++){
             cin>>yoko[j][i];
            }
           }
      }
   
      int a=bfs();
      /*for(int j=0;j<H;j++){
           for(int i=0;i<W;i++){
            cout<<d[i][j];
           }
           cout<<endl;
           }*/
       
      if(a==-1)cout<<0<<endl;
      else cout<<a+1<<endl;
     }
     return 0;
}

C++: #include <iostream>
#include <queue>
using namespace std;

int main(){
    while(true){
        int w, h;
        int ver[30][29], hor[29][30];
        int maze[30][30] = {0};
        queue<pair<int, int> > pos;
        int route=0;
        cin >> w >> h;
        if(!(w||h)) break;
        for(int i=0;i<h-1;++i){
            for(int j=0;j<w-1;++j){
                cin >> ver[i][j];
            }
            for(int j=0;j<w;++j){
                cin >> hor[i][j];
            }
        }
        for(int j=0;j<w-1;++j){
            cin >> ver[h-1][j];
        }
        pos.push(make_pair(0,0));
        maze[0][0] = 1;
        while(!pos.empty()){
            int x=pos.front().first, y=pos.front().second;
            if(x==w-1 && y==h-1){
                route = maze[y][x];
                break;
            }
            pos.pop();
            if(x+1<w && ver[y][x]==0 && maze[y][x+1]==0){
                pos.push(make_pair(x+1, y));
                maze[y][x+1] = maze[y][x]+1;
            }
            if(y+1<h && hor[y][x]==0 && maze[y+1][x]==0){
                pos.push(make_pair(x, y+1));
                maze[y+1][x] = maze[y][x]+1;
            }
            if(x-1>=0 && ver[y][x-1]==0 && maze[y][x-1]==0){
                pos.push(make_pair(x-1, y));
                maze[y][x-1] = maze[y][x]+1;
            }
            if(y-1>=0 && hor[y-1][x]==0 && maze[y-1][x]==0){
                pos.push(make_pair(x, y-1));
                maze[y-1][x] = maze[y][x]+1;
            }
        }
        cout << route << endl;
    }
}