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 (pq PQStatus) Len() int {
	return len(pq)
}
func (pq PQStatus) Less(i, j int) bool {
	if pq[i].Turn == pq[j].Turn {
		return pq[i].Person.Distance() < pq[j].Person.Distance()
	}
	return pq[i].Turn < pq[j].Turn
}

func (pq PQStatus) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
}

func (pq *PQStatus) Push(x interface{}) {
	item := x.(*Status)
	*pq = append(*pq, item)
}

func (pq *PQStatus) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	*pq = old[0 : n-1]
	return item
}

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)
	//heap.Init(&pq)
	//heap.Push(&pq, start)
	//pq.Push(start)
	pq = append(pq, start)
	dx := []int64{0, 1, 0, -1}
	dy := []int64{1, 0, -1, 0}
	memo := make(map[PersonPosition]int64, 0)
	ans := int64(101)
	for pq.Len() > 0 {
		//now := heap.Pop(&pq).(*Status)
		//now := pq.Pop().(*Status)
		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 += 1
			if next.Turn <= 100 {
				//heap.Push(&pq, next)
				//pq.Push(next)
				pq = append(pq, next)
			}
		}
	}
	if ans == 101 {
		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 <cstdio>
#include <queue>
#include <map>
#include <algorithm>
#define Z(n)get<n>(z)
#define M make_pair
#define F first
#define S second
using namespace std;
typedef pair<int,int> pii;
typedef tuple<pii,pii,int> T;
int t[51][51],dx[]={-1,0,1,0},dy[]={0,-1,0,1},a,b,x,y,X,Y,i,j,k;
int main(){
	for(;scanf("%d%d",&a,&b),a;){
		map<pair<pii,pii>,int>m;
		scanf("%d%d%d%d",&x,&y,&X,&Y);x--,y--,X--,Y--;
		for(j=0;j<b;j++)for(i=0;i<a;i++)scanf("%d",t[i]+j);
		queue<T>q;
		m[M(M(x,y),M(X,Y))]=1;
		for(q.push(make_tuple(M(x,y),M(X,Y),0));!q.empty();){
			T z=q.front();q.pop();
			if(Z(0)==Z(1)){printf("%d\n",get<2>(z));goto OK;}
			if(Z(2)<100)for(i=0;i<4;i++){
				pii c1=make_pair(Z(k=0).F+dx[i],Z(0).S+dy[i]);
				if(!(0<=c1.F&&c1.F<a&&0<=c1.S&&c1.S<b&&!t[c1.F][c1.S]))c1=Z(0),k|=1;
				pii c2=make_pair(Z(1).F+dx[(i+2)%4],Z(1).S+dy[(i+2)%4]);
				if(!(0<=c2.F&&c2.F<a&&0<=c2.S&&c2.S<b&&!t[c2.F][c2.S]))c2=Z(1),k|=2;
				if(k<3&&!m[M(c1,c2)]){
					q.push(make_tuple(c1,c2,Z(2)+1));
					m[M(c1,c2)]=1;
				}
			}
		}
		puts("NA");
		OK:;
	}
}

C++: #include<bits/stdc++.h>
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using namespace std;
typedef pair<int,int> pii;
typedef pair<pii,pii> state;

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

int main(){
  int w,h;
  while(cin >> w >> h, w){
    int ax,ay,bx,by;
    cin >> ax >> ay >> bx >> by;
    state init(pii(ax,ay),pii(bx,by));
    
    vector< vector<int> > g(h+2,vector<int>(w+2,1));
    rep(i,h)rep(j,w){
      cin >> g[i+1][j+1];
    }

    queue<state> q;
    q.push(init);
    map<state, int> d;
    d[init] = 0;

    int ans = 1000;
    while(q.size()){
      state cur = q.front(); q.pop();
      if(ax==bx && ay==by){
	ans = d[cur]; break;
      }

      if(d[cur]==99)continue;
      ax = cur.first.first; ay = cur.first.second;
      bx = cur.second.first; by = cur.second.second;

      rep(a,4){
	int nax = ax+dx[a], nay = ay+dy[a];
	int nbx = bx-dx[a], nby = by-dy[a];

	if(g[nay][nax])nay = ay, nax = ax;
	if(g[nby][nbx])nby = by, nbx = bx;

	state nxt(pii(nax,nay),pii(nbx,nby));
	if(d.count(nxt))continue;

	d[nxt] = d[cur] + 1;
	q.push(nxt);
      }
    }

    if(ans>=100)cout << "NA" << endl;
    else cout << ans << endl;
  }
}

C++: #include<stdio.h>
#include<iostream>
#include<queue>
#include<string.h>
using namespace std;
struct oza{
	int x;
	int y;
};
int A[50][50][50][50];
int main(){
	oza k;
	oza t;
	queue<oza> ka;
	queue<oza> ta;
	queue<int> Z;
	int  w,h,b;
	int d=0,c=0,i=0,j=0,l=-1,D[52][52];
	int tx[4]={ 1, 0,-1,0 };       
	int kx[4]={-1, 0, 1,0 };
	int ty[4]={ 0, 1, 0,-1 };
	int ky[4]={ 0, -1, 0,1};
	scanf("%d %d",&w,&h);
	while(w!=0&&h!=0){
	memset(A,0,sizeof(A));
		for(i=0;i<=h+1;i++){
		for(j=0;j<=w+1;j++){
		D[i][j]=1; //??¨????????????????????\?????? 
		}
	}

	scanf("%d %d",&t.x,&t.y);
	scanf("%d %d",&k.x,&k.y);
	for(i=1;i<=h;i++){
		for(j=1;j<=w;j++){
		scanf("%d",&D[i][j]);
		}
	}
	ta.push(t);
	ka.push(k);
	Z.push(c);
		if(t.x==k.x&&t.y==k.y){
			d=-1;
		}
	while(d!=-1){
		l++;
		if(l==4){
		l=0;
		t=ta.front();
		k=ka.front();
		ka.pop();
		ta.pop();
		Z.pop();
		A[t.x][t.y][k.x][k.y]=1;
		}
		if(c==100||Z.empty()){
			printf("NA");
		break;
		}
	
		// ?????\????????????????????¨?????¨??????
		t=ta.front();
		k=ka.front();
		c=Z.front();
		
		t.x=t.x+tx[l];
		t.y=t.y+ty[l];
		k.x=k.x+kx[l];
		k.y=k.y+ky[l];
		
		if(D[t.x][t.y]==1){
		t.x=t.x-tx[l];
		t.y=t.y-ty[l];
		}
		if(D[k.x][k.y]==1){
		k.x=k.x-kx[l];
		k.y=k.y-ky[l];
		}
		if(A[t.x][t.y][k.x][k.y]==1){
			continue;
		}
		
		ta.push(t);
		ka.push(k);
		c=c+1;
		Z.push(c);
		
		if(t.x==k.x&&t.y==k.y){
			printf("%d\n",Z.back());
			break;
		}	
		
		
	}
	while(!ka.empty()){
	ka.pop();
	ta.pop();
	Z.pop();
	}
	c=0;
	l=-1;
	scanf("%d %d",&w,&h);
	}	
	return 0;

}