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 <bits/stdc++.h>
#include <unordered_map>
// #include <unordered_set>
using namespace std;
class Pos {
  public:
    int y;
    int x;
    size_t hashed;
    Pos(int _y, int _x):
      y(_y),
      x(_x) {
      hashed = 0;
    }
    bool operator==(Pos right) const {
      return (y == right.y && x == right.x);
    }
    // bool operator<(Pos right) const {
    // }
};

namespace std {
  template <>
  struct hash<Pos> {
    size_t operator()(Pos const &pos) const {
      return pos.hashed;
    }
  };
}

int main() {
  int H, W;
  while(cin >> W >> H, W || H) {
    unordered_map<Pos, unordered_set<Pos> > loads;
    for(int h = 0; h < H; ++h) {
      for(int w = 0; w < W - 1; ++w) {
        bool isHrizWall;
        cin >> isHrizWall;
        if(!isHrizWall) {
          Pos a = Pos(h, w);
          Pos b = Pos(h, w + 1);
          loads[a].insert(b); 
          loads[b].insert(a);
        }
      }
      if(h < H - 1) for(int w = 0; w < W; ++w) {
        bool isVertWall;
        cin >> isVertWall;
        if(!isVertWall) {
          Pos a = Pos(h, w);
          Pos b = Pos(h + 1, w);
          loads[a].insert(b);
          loads[b].insert(a);
        }
      }
    }
    Pos goal = Pos(H - 1, W - 1);
    unordered_map<Pos, int> marked;
    queue<Pos> bfq;
    bfq.push(Pos(0, 0));
    marked[Pos(0, 0)] = 1;
    bool answered = false;
    while(!bfq.empty()) {
      Pos crtPos = bfq.front();
      bfq.pop();
      if(crtPos == goal) {
        answered = true;
        cout << marked[crtPos] << endl;
        break;
      }
      for(auto i = loads[crtPos].begin(); i != loads[crtPos].end(); ++i) {
        // cout << (*i).y << ',' << (*i).x << endl;
        if(marked.count(*i) == 0) {
          marked[*i] = marked[crtPos] + 1;
          bfq.push(*i);
        }
      }
    }
    if(!answered) cout << 0 << endl;
  // for(auto i = marked.begin(); i != marked.end(); ++i) {
  //   cout << (*i).first.y << ',' << (*i).first.x << ':' << (*i).second << endl;
  // }
  //
  // for(auto i = loads.begin(); i != loads.end(); ++i) {
  //   for(auto j = i->second.begin(); j != i->second.end(); ++j) {
  //     cout << i->first.y << ',' << i->first.x << ':' << j->y << ',' << j->x << ' ';
  //   }
  //   cout << endl;
  // }
  }
  return 0;
}

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

static const int inf = 1000;

struct node{
  int x;
  int y;
};



int hor[36][36] = {{}};
int vir[36][36] = {{}};
int d[36][36] ;
int h,w,a = 0;

void bfs(int r,int s){

  queue <node> q;
  node locate; 
  node u,t;

  locate.y = r;
  locate.x = s;

  // cout << "lx = " << locate.x << ' ' << "ly = " << locate.y << endl;

  for(int i = 0;i < h;i++){
    for(int j = 0;j < w;j++){
      d[i][j] = inf;
    }
  }

  q.push(locate);

  d[0][0] = 1;

  while(!q.empty()){
    u = q.front(); q.pop();
    a++;
    if(hor[u.y][u.x] != 1 && u.y < h - 1){
      if(d[u.y][u.x] + 1 < d[u.y + 1][u.x]) d[u.y + 1][u.x] = d[u.y][u.x] + 1;
      t.x = u.x;
      t.y = u.y + 1; 
      q.push(t);
     
    }
    if(vir[u.y][u.x] != 1 && u.x < w - 1){
      if(d[u.y][u.x] + 1 < d[u.y][u.x + 1]) d[u.y][u.x + 1] = d[u.y][u.x] + 1;
      t.y = u.y;
      t.x = u.x + 1;
      q.push(t);
    }

    if((hor[u.y - 1][u.x] != 1) &&( u.y > 0 )&& (( vir[u.y][u.x] == 1) ||( hor[u.y][u.x] == 1))){
      if(d[u.y][u.x] + 1 <  d[u.y - 1][u.x]) d[u.y - 1][u.x] = d[u.y][u.x] + 1;
      t.x = u.x;
      t.y = u.y - 1; 
      q.push(t);
     
    }

    if((vir[u.y][u.x - 1] != 1) &&( u.x > 0 ) && (( vir[u.y][u.x] == 1) ||( hor[u.y][u.x] == 1))){
      if(d[u.y][u.x] + 1 < d[u.y][u.x - 1]) d[u.y][u.x - 1] = d[u.y][u.x] + 1;
      t.y = u.y;
      t.x = u.x - 1;
      q.push(t);
    }

    if(a > 8000000) {
      d[h - 1][w - 1] = 0;
      a = 0;
      break;
    }
    //   cout << "x = " << u.x << ' ' << "y = " << u.y << endl;
    if(u.x == w - 1 && u.y == h - 1){
      a = 0;
      break;
    }
  }




}


int main(){

   while(1){
    cin >> w >> h;

    // cout << " w = " << w << ' ' << "h = " << h << endl; 
     if(w == 0 && h == 0) break;

    for(int i = 0;i < h - 1;i++){
      for(int j = 0;j < w - 1;j++) cin >> vir[i][j];
      for(int j = 0;j < w ;j++) cin >> hor[i][j];
    }

    for(int j = 0;j < w - 1;j++) cin >> vir[h - 1][j];

   

    bfs(0,0);
    // cout << "a = " << a << endl;
    cout << d[h - 1][w - 1] << endl;

    for(int i = 0;i < 36;i++){
      for(int j = 0;j < 36;j++){
	vir[i][j] = 0;
	hor[i][j] = 0;
	d[i][j] = 0;

      }
    }
     }
}