Go: package main

import (
	"fmt"
	"math"
)

type Position struct {
	X int64
	Y int64
}

func (one Position) Distance(another Position) int64 {
	return int64(math.Abs(float64(one.X-another.X)) + math.Abs(float64(one.Y-another.Y)))
}

type PersonPosition struct {
	Takayuki Position
	Kazuyuki Position
}

func (one PersonPosition) Distance() int64 {
	return one.Takayuki.Distance(one.Kazuyuki)
}

type Status struct {
	Person PersonPosition
	Turn   int64
}

type PQStatus []*Status

func solve(h, w int64) {
	var tx, ty, kx, ky int64
	fmt.Scan(&tx, &ty, &kx, &ky)
	tx--
	ty--
	kx--
	ky--
	m := make([][]int64, h)
	for i := range m {
		m[i] = make([]int64, w)
		for j := int64(0); j < w; j++ {
			fmt.Scan(&m[i][j])
		}
	}
	start := &Status{Person: PersonPosition{Takayuki: Position{X: tx, Y: ty}, Kazuyuki: Position{X: kx, Y: ky}}, Turn: 0}
	pq := make(PQStatus, 0)
	pq = append(pq, start)
	dx := []int64{0, 1, 0, -1}
	dy := []int64{1, 0, -1, 0}
	memo := make(map[PersonPosition]int64, 0)
	ans := int64(102)
	for len(pq) > 0 {
		now := pq[0]
		pq = pq[1:]
		if now.Person.Distance() == 0 && ans > now.Turn {
			ans = now.Turn
		}
		if ans <= now.Turn {
			continue
		}

		if _, ok := memo[now.Person]; ok {
			continue
		}
		memo[now.Person] = now.Turn

		for i := 0; i < 4; i++ {
			next := &Status{}
			*next = *now
			next.Person.Kazuyuki.X += dx[i]
			next.Person.Kazuyuki.Y += dy[i]
			if next.Person.Kazuyuki.X < 0 || next.Person.Kazuyuki.X >= w ||
				next.Person.Kazuyuki.Y < 0 || next.Person.Kazuyuki.Y >= h ||
				m[next.Person.Kazuyuki.Y][next.Person.Kazuyuki.X] == 1 {
				next.Person.Kazuyuki.X -= dx[i]
				next.Person.Kazuyuki.Y -= dy[i]
			}
			next.Person.Takayuki.X -= dx[i]
			next.Person.Takayuki.Y -= dy[i]
			if next.Person.Takayuki.X < 0 || next.Person.Takayuki.X >= w ||
				next.Person.Takayuki.Y < 0 || next.Person.Takayuki.Y >= h ||
				m[next.Person.Takayuki.Y][next.Person.Takayuki.X] == 1 {
				next.Person.Takayuki.X += dx[i]
				next.Person.Takayuki.Y += dy[i]
			}
			next.Turn++
			if next.Turn <= 100 {
				pq = append(pq, next)
			}
		}
	}
	if ans == 102 {
		fmt.Println("NA")
	} else {
		fmt.Println(ans)
	}
}

func main() {
	var h, w int64
	for {
		fmt.Scan(&h, &w)
		if h == 0 && w == 0 {
			break
		}
		solve(h, w)
	}
}

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

#define INF (1 << 25)

using namespace std;

vector<vector<vector<vector<int> > > > dp;

vector<vector<int> > M;

int H, W, sx1, sy1, sx2, sy2;

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

int bfs()
{
    dp = vector<vector<vector<vector<int> > > >(H, vector<vector<vector<int> > >(W, vector<vector<int> >(H, vector<int>(W, INF)))); dp[sy1][sx1][sy2][sx2] = 0;
    
    queue<pair<pair<pair<int, int>, pair<int, int> >, int> > que; que.push(make_pair(make_pair(make_pair(sx1, sy1), make_pair(sx2, sy2)), 0));
    
    while(!que.empty())
    {
        int x1 = que.front().first.first.first;
        int y1 = que.front().first.first.second;
        int x2 = que.front().first.second.first;
        int y2 = que.front().first.second.second;
        
        int turn = que.front().second;
        
        que.pop();
        
        for(int dir = 0; dir < 4; dir++)
        {
            int tx1 = x1 + dx[dir]; if(tx1 < 0 || tx1 > W) { tx1 -= dx[dir]; }
            int ty1 = y1 + dy[dir]; if(ty1 < 0 || ty1 > H) { ty1 -= dy[dir]; }
            int tx2 = x2 - dx[dir]; if(tx2 < 0 || tx2 > W) { tx2 += dx[dir]; }
            int ty2 = y2 - dy[dir]; if(ty2 < 0 || ty2 > H) { ty2 += dy[dir]; }
            
            if(M[ty1][tx1] == 1) { tx1 -= dx[dir]; ty1 -= dy[dir]; }
            if(M[ty2][tx2] == 1) { tx2 += dx[dir]; ty2 += dy[dir]; }
            
            if(tx1 == tx2 && ty1 == ty2) { return turn + 1; }
            
            if(dp[ty1][tx1][ty2][tx2] == INF)
            {
                dp[ty1][tx1][ty2][tx2] = turn + 1;
                
                que.push(make_pair(make_pair(make_pair(tx1, ty1), make_pair(tx2, ty2)), turn + 1));
            }
        }
    }
    
    return -1;
}

int main()
{
    while(true)
    {
        cin >> W >> H;
        
        if(H == 0 && W == 0) { break; }
        
        M = vector<vector<int> >(H, vector<int>(W));
        
        cin >> sx1 >> sy1 >> sx2 >> sy2;
        
        sx1--; sy1--; sx2--; sy2--;
        
        for(int i = 0; i < H; i++)
        {
            for(int j = 0; j < W; j++)
            {
                cin >> M[i][j];
            }
        }
        
        int Ans = bfs();
        
        if(Ans == -1)
        {
            cout << "NA" << endl;
        }
        else
        {
            cout << Ans << endl;
        }
    }
    
    return 0;
}

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

const int INF=100000000;

class Point{
public:
  int tx;
  int ty;
  int kx;
  int ky;
};

int main(){
  while(true){
    int X,Y;
    cin>>X>>Y;
    if(X==0&&Y==0){
      break;
    }
    char F[X+1][Y+1];
    int D[X][Y];
    for(int x=1;x<=X;x++){
      for(int y=1;y<=Y;y++){
        D[x][y]=INF;
      }
    }
    int tx,ty,kx,ky;
    cin>>tx>>ty;
    cin>>kx>>ky;
    D[tx][ty]=0;
    D[kx][ky]=0;

    for(int x=0;x<=X+1;x++){
      for(int y=0;y<=Y+1;y++){
        F[x][y]=1;
      }
    }
    int a;
    for(int x=1;x<=X;x++){
      for(int y=1;y<=Y;y++){
        cin>>a;
        F[x][y]=a;
      }
    }


    queue<Point> que;

    Point p;
    p.tx=tx;
    p.ty=ty;
    p.kx=kx;
    p.ky=ky;
    que.push(p);

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

      if(p.tx==p.kx&&p.ty==p.ky){
        if(D[p.tx][p.ty]>100){
          cout<<"NA"<<endl;
          break;
        }
        cout<<D[p.tx][p.ty]<<endl;
        break;
      }

      if(D[p.tx-1][p.ty]==INF&&D[p.kx+1][p.ky]==INF){
        Point q;
        q.tx=p.tx-1;
        q.ty=p.ty;
        q.kx=p.kx+1;
        q.ky=p.ky;
        if(F[q.tx][q.ty]==1){
          q.tx=q.tx+1;
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
        }else
        if(F[q.kx][q.ky]==1){
          q.kx=q.kx-1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }else{
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }
        que.push(q);
      }

      if(D[p.tx+1][p.ty]==INF&&D[p.kx-1][p.ky]==INF){
        Point q;
        q.tx=p.tx+1;
        q.ty=p.ty;
        q.kx=p.kx-1;
        q.ky=p.ky;
        if(F[q.tx][q.ty]==1){
          q.tx=q.tx+1;
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
        }else
        if(F[q.kx][q.ky]==1){
          q.kx=q.kx-1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }else{
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }
        que.push(q);
      }

      if(D[p.tx][p.ty+1]==INF&&D[p.kx][p.ky-1]==INF){
        Point q;
        q.tx=p.tx;
        q.ty=p.ty+1;
        q.kx=p.kx;
        q.ky=p.ky-1;
        que.push(q);
        if(F[q.tx][q.ty]==1){
          q.tx=q.tx+1;
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
        }else
        if(F[q.kx][q.ky]==1){
          q.kx=q.kx-1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }else{
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }
        que.push(q);
      }

      if(D[p.tx][p.ty-1]==INF&&D[p.kx][p.ky+1]==INF){
        Point q;
        q.tx=p.tx;
        q.ty=p.ty-1;
        q.kx=p.kx;
        q.ky=p.ky+1;
        if(F[q.tx][q.ty]==1){
          q.tx=q.tx+1;
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
        }else
        if(F[q.kx][q.ky]==1){
          q.kx=q.kx-1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }else{
          D[q.kx][q.ky]=D[p.kx][p.ky]+1;
          D[q.tx][q.ty]=D[p.tx][p.ty]+1;
        }
        que.push(q);
      }

    }
  }

  return 0;
}