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 <sstream>
#include <string>
#include <vector>
#include <map>
#include <algorithm>
#include <iostream>
#include <utility>
#include <set>
#include <cctype>
#include <queue>
#include <stack>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <climits>
using namespace std;
#define INF 100000000
#define MAXH 32
#define MAXW 32
typedef long long ll;
typedef pair<int, int> P;

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

int w, h;
// hは縦方向 wは横方向
int wallh[MAXH][MAXW], wallw[MAXH][MAXW];
int d[MAXH][MAXW];

int main(void) {
    while (1) {
        cin >> w >> h;
        if (w == 0 && h == 0) break;
        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w-1; j++) {
                cin >> wallw[i][j];
            }
            if (i < h-1) {
                for (int j = 0; j < w; j++) {
                    cin >> wallh[i][j];
                }
            } else {
                for (int j = 0; j < w; j++) {
                    wallh[i][j] = 1;
                }
            }
        }
        for (int i = 0; i < h; i++) {
            for (int j = 0; j < w; j++) {
                d[i][j] = -1;
            }
        }
        d[0][0] = 1;
        queue<P> que;
        que.push(make_pair(0, 0));
        while (!que.empty()) {
            P now = que.front(); que.pop();
            int y = now.first, x = now.second;
            // 右方向
            if (x < w-1 && wallw[y][x] == 0) {
                int nx = x + 1;
                int ny = y;
                if (d[ny][nx] < 0) {
                    d[ny][nx] = d[y][x] + 1;
                    que.push(make_pair(ny, nx));
                }
            }
            // 上方向
            if (0 < y && wallh[y-1][x] == 0) {
                int nx = x;
                int ny = y - 1;
                if (d[ny][nx] < 0) {
                    d[ny][nx] = d[y][x] + 1;
                    que.push(make_pair(ny, nx));
                }
            }
            // 左方向
            if (0 < x && wallw[y][x-1] == 0) {
                int nx = x - 1;
                int ny = y ;
                if (d[ny][nx] < 0) {
                    d[ny][nx] = d[y][x] + 1;
                    que.push(make_pair(ny, nx));
                }
            }
            // 下方向
            if (y < h-1 && wallh[y][x] == 0) {
                int nx = x;
                int ny = y + 1;
                if (d[ny][nx] < 0) {
                    d[ny][nx] = d[y][x] + 1;
                    que.push(make_pair(ny, nx));
                }
            }
        }
        if (d[h-1][w-1] < 0) cout << 0 << endl;
        else cout << d[h-1][w-1] << endl;
    }
    return 0;
}

C++: #include<cstdio>
#include<queue>
#include<algorithm>
using namespace std;
typedef pair<int,int> PA;
int main(){
  int w,h,maze[61][61];
  while(1){
    scanf("%d %d",&w,&h);
    if(w==0&&h==0) break;
    fill_n(*maze,61*61,0);
    for(int i=0;i<h*2-1;i++){
      for(int j=0;j<w*2-1;j++){
	if( (i+j)%2 == 1) scanf(" %d",&maze[i][j]);
      }
    }
    queue<PA> que;
    int dx[4] = {2,-2,0,0};
    int dy[4] = {0,0,2,-2};
    que.push(PA(0,0));
    maze[0][0] = 1;
    while(!que.empty()){
      PA p = que.front();
      que.pop();
      for(int i=0;i<4;i++){
	int y = p.first + dy[i];
	int x = p.second + dx[i];
	int wy = p.first + dy[i]/2;
	int wx = p.second + dx[i]/2;
	if(x<0||y<0||x>=w*2-1||y>=h*2-1||maze[y][x]!=0||maze[wy][wx]==1)
	  continue;
	maze[y][x] = maze[p.first][p.second]+1;
	que.push(PA(y,x));
      }
    }
    printf("%d\n",maze[h*2-2][w*2-2]);
  }
  return (0);
}