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<cstdio>
#include<math.h>
#include<string>
#include<algorithm>
#include<functional>
#include<vector>
#include<set>
#include<queue>
#include<map>
#define INF 999999
#define EPS 1.0e-6

using namespace std;

typedef long long ll;
typedef pair<int, int> P;
typedef pair<int, P> PP;


int w, h;

int yoko[40][40];
int tate[40][40];
int visited[40][40];

int main()
{
	while (cin >> w >> h) {
		if (w == 0 && h == 0)return 0;

		int a;

	
		for (int i = 0; i < 40; i++) {
			for (int j = 0; j < 40; j++) {
				tate[i][j] = 1;
				yoko[i][j] = 1;
				visited[i][j] = 0;
			}
		}
		
		

		for (int i = 1; i < 2 * h; i++) {
			if (i % 2 == 1) {
				for (int j = 1; j <= w - 1; j++) {
					cin >> a;
					yoko[i / 2][j] = a;
				}
			}
			else {
				for (int j = 0; j < w; j++) {
					cin >> a;
					tate[i / 2][j] = a;
				}
			}
		}

		/*
		for (int i = 0; i <= h; i++) {
			for (int j = 0; j < w; j++) {
				cout << tate[i][j] << " ";
			}
			cout << endl;
		}
		cout << endl;
		for (int i = 0; i <= h; i++) {
			for (int j = 0; j <= w; j++) {
				cout << yoko[i][j] << " ";
			}
			cout << endl;
		}
		*/
		visited[1][1] = 1;

		queue<P>q;
		q.push(P(1, 1));

		while (!q.empty()) {
			P p = q.front();
			q.pop();

			int x = p.first;
			int y = p.second;

			//cout << x << " " << y << " " << visited[x][y] << endl;
			if (yoko[x-1][y-1]==0&&visited[x][y-1]==0) {
				q.push(P(x, y - 1));
				visited[x][y - 1] = visited[x][y] + 1;
			}
			if (yoko[x-1][y] == 0 && visited[x][y+1] == 0) {
				q.push(P(x, y + 1));
				visited[x][y + 1] = visited[x][y] + 1;
			}
			if (tate[x-1][y-1] == 0 && visited[x - 1][y] == 0) {
				q.push(P(x-1, y));
				visited[x-1][y] = visited[x][y] + 1;
			}
			if (tate[x][y-1] == 0 && visited[x + 1][y] == 0) {
				q.push(P(x + 1, y));
				visited[x + 1][y] = visited[x][y] + 1;
			}


			

		}



		cout << visited[h][w] << endl;

	}


	return 0;
}

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

//N 点、目的地の数
//M 辺、経路の数
//S 始点、Sからの距離を一覧で出す
//A[] 各辺の始点
//B[] 各辺の終点
//C[] 各辺の距離
//dist[] Sからの距離一覧
//G[]<int><int> グラフ、辺の集合

int intmax = 1000000007;
int N, M, S, A, B, C, h, w;
int cnt=0;
int dist[100009];
vector<pair<int, int>> G[100009];
priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> Q;

int main() {

	while (1) {
		cin >> h >> w;
		if (h + w == 0) break;

		for(int i=0;i<100009;i++) G[i].resize(0);
      	while (!Q.empty()) Q.pop();

		// グラフを入力する
		//scanf("%d%d", &N, &M);
		N = h * w;
		M = (w - 1)*h + w * (h - 1);
		for (int i = 0; i < 2 * w - 1; i++) {
          //cout<< "i" << i <<endl;
			if (i % 2 == 0) {
				for (int j = 1;j < h;j++) {
					A = h * i/2 + j;
					B = h * i/2 + j + 1;
					cin >> C;
                  	C=C*intmax+1;
					G[A].push_back(make_pair(B, C));
					G[B].push_back(make_pair(A, C));
                    //if(1) cout<< A << " " << B <<endl;
				}
			}
			else {
				for (int j = 1;j <= h;j++) {
					A = h * (i/2) + j;
					B = h * (i/2 + 1) + j;
					cin >> C;
                  	C=C*intmax+1;
					G[A].push_back(make_pair(B, C));
					G[B].push_back(make_pair(A, C));
                  	//if(1) cout<< A << " " << B <<endl;
				}
			}

		}
		S = 1;
      
      	cnt++;
      	//cout<< "rap " << cnt <<endl;

		// 距離を初期化する
		for (int i = 1; i <= N; i++) dist[i] = intmax;

		// 優先度付きキューには (距離, 頂点番号) の組を入れる
		Q.push(make_pair(0, S));
		dist[S] = 1;
		while (!Q.empty()) {
			int pos = Q.top().second; Q.pop();
			for (int i = 0; i < G[pos].size(); i++) {
				int to = G[pos][i].first, cost = G[pos][i].second;
				if (dist[to] > dist[pos] + cost) {
					dist[to] = dist[pos] + cost;
					Q.push(make_pair(dist[to], to));
				}
			}
		}

		// 距離を出力する
		if (dist[h*w] == intmax) cout << "0" << endl;
		else cout << dist[h*w] << endl;

	}
	return 0;
}