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++: /*
  Amazing Mazes
  http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=1166&lang=jp
*/

#include <iostream>
#include <queue>

using namespace std;

int main(void){
  while(1){
    int isPassed[30][30]; // ??¢?´¢?????????????????????????????? 0????????¢?´¢???1?????¢?´¢???
    int vwalls[30][30];   // ?????????????£??????????
    int hwalls[30][30];   // ?¨???????????£??????????
    int height = 0;
    int width = 0;
    int min[30][30];
    queue< pair<int,int> > q;

    int x = 0;
    int y = 0;
    bool noans = false;
    int ans = 1;

    cin >> width;
    cin >> height;

    if(height == 0 && width == 0) return 0;

    for(int i = 0 ; i < 30 ; i++){
      for(int j = 0 ; j < 30 ; j++){
        isPassed[i][j] = 0;
        vwalls[i][j] = 0;
        hwalls[i][j] = 0;
      }
    }

    for(int j = 0 ; j < width - 1 ; j++){
      cin >> vwalls[0][j];
    }

    for(int i = 1 ; i < height ; i++){
      for(int j = 0 ; j < width ; j++){
        cin  >> hwalls[i-1][j];
      }

      for(int j = 0 ; j < width - 1 ; j++){
        cin >> vwalls[i][j];
      }
    }

    isPassed[0][0] = 1;
    min[0][0] = 0;
    x = 0; y = 0;
    ans = 1;

    while(!(y == width - 1 && x == height - 1) && noans == false){

      // ???????§????
      if(y < width - 1 && vwalls[x][y] == 0 && isPassed[x][y+1] == 0){
        q.push(make_pair(x, y+1));
        isPassed[x][y+1] = 1;
        min[x][y+1] = min[x][y] + 1;
      }

      // ???????§????
      if(y > 0 && vwalls[x][y-1] == 0 && isPassed[x][y-1] == 0){
        q.push(make_pair(x, y-1));
        isPassed[x][y-1] = 1;
        min[x][y-1] = min[x][y] + 1;
      }

      // ???????§????
      if(x > 0 && hwalls[x-1][y] == 0 && isPassed[x-1][y] == 0){
        q.push(make_pair(x-1, y));
        isPassed[x-1][y] = 1;
        min[x-1][y] = min[x][y] + 1;
      }

      // ???????§????
      if(x < height - 1 && hwalls[x][y] == 0 && isPassed[x+1][y] == 0){
        q.push(make_pair(x+1, y));
        isPassed[x+1][y] = 1;
        min[x+1][y] = min[x][y] + 1;
      }

      if(q.empty() == true){
        noans = true;
      }else{
        pair<int,int> tmppair;
        x = q.front().first;
        y = q.front().second;
        q.pop();
      }

    }

    if(noans == false){
      cout << min[height-1][width-1] + 1 << endl;
    }else{
      cout << 0 << endl;
    }
  }
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <queue>

using namespace std;

namespace Solver {

    int w, h;
    vector<vector<int>> vw, hw, field;
    inline bool Read() {
        cin >> w >> h;
        if (h == 0) return false;

        vw.resize(h);
        hw.resize(h - 1);
        for (int i = 0; i < h * 2 - 1; i++) {
            int idx = i / 2;
            if (i % 2 == 0) {
                vw[idx].resize(w - 1);
                for (int j = 0; j < w - 1; j++) {
                    cin >> vw[idx][j];
                }
            } else {
                hw[idx].resize(w);
                for (int j = 0; j < w; j++) {
                    cin >> hw[idx][j];
                }
            }
        }

        return true;
    }

    const int dx[] = {0, 1, 0, -1}, dy[] = {-1, 0, 1, 0};
    inline void Work() {
        vector<vector<int>> field(h);
        for (int y = 0; y < h; y++) {
            field[y].resize(w);
            for (int x = 0; x < w; x++) {
                field[y][x] = -1;
            }
        }

        queue<pair<int, int>> que;
        que.push(pair<int, int>(0, 0));
        field[0][0] = 0;
        while (!que.empty()) {
            pair<int, int> pos = que.front();
            que.pop();
            int x = pos.first, y = pos.second;
            for (int k = 0; k < 4; k++) {
                int nx = x + dx[k], ny = y + dy[k];

                if (nx < 0 || nx >= w || ny < 0 || ny >= h || field[ny][nx] != -1) continue;

                if (dx[k] == 1 && vw[ny][nx - 1] == 1) continue;
                if (dx[k] == -1 && vw[ny][nx] == 1) continue;
                if (dy[k] == 1 && hw[ny - 1][nx] == 1) continue;
                if (dy[k] == -1 && hw[ny][nx] == 1) continue;

                field[ny][nx] = field[y][x] + 1;
                que.push(pair<int, int>(nx, ny));
            }
        }

        if (field[h - 1][w - 1] == -1) {
            cout << 0 << endl;
        } else {
            cout << field[h - 1][w - 1] + 1 << endl;
        }
    }

    inline void Solve() {
        while (Read()) Work();
    }
}

int main() {
    Solver::Solve();
}