Go: package main

import (
	"bufio"
	"os"
	"strconv"
	"strings"
	"math"
	"fmt"
)

var scanner = bufio.NewScanner(os.Stdin)

func main() {
	dd := make([][]int, 1000)
	for i := range dd {
		dd[i] = make([]int, 1000)
	}
	num := make([]int,1000)
	inv := make([]int, 1001)
	x := make([]int, 1000)
	y := make([]int, 1000)
	vv := make([]int, 1000)
	nowt := make([]float64, 1000)
	rev := make([]int, 1000)
	for scanner.Scan() {
		n, _ := strconv.Atoi(scanner.Text())
		if n == 0 {
			break
		}
		for i := 0; i < n; i++ {
			scanner.Scan()
			buf1 := strings.Split(scanner.Text(), " ")
			num[i], _ = strconv.Atoi(buf1[0])
			x[i], _ = strconv.Atoi(buf1[1])
			y[i], _ = strconv.Atoi(buf1[2])
			inv[num[i]] = i
		}
		for i := 0; i < n; i++ {
			for j := 0; j < n; j++ {
				dd[i][j]=(x[i]-x[j])*(x[i]-x[j])+(y[i]-y[j])*(y[i]-y[j])
			}
		}
		scanner.Scan()
		m, _ := strconv.Atoi(scanner.Text())
		for i := 0; i < m; i++ {
			scanner.Scan()
			buf2 := strings.Split(scanner.Text(), " ")
			c, _ := strconv.Atoi(buf2[0])
			d, _ := strconv.Atoi(buf2[1])
			c = inv[c]
			d = inv[d]
			for j := 0; j < n; j++ {
				vv[j] = 0
				nowt[j]=999999999
				rev[j]=-1
			}
			nowt[c]=0
			for j := 0; j < n; j++ {
				M := 99999999
				at := 0
				for k := 0; k < n; k++ {
					if vv[k] == 0 && float64(M) > nowt[k] {
						M=int(nowt[k])
						at = k
					}
				}
				if M > 90000000 {
					break
				}
				vv[at]=1
				for k := 0; k < n; k++ {
					if vv[k] == 0 && dd[at][k]<=2500&&nowt[k]>nowt[at]+math.Sqrt(float64(dd[at][k])) {
						nowt[k]=nowt[at]+math.Sqrt(float64(dd[at][k]))
						rev[k] = at
					}
				}
			}
			if vv[d] == 0 {
				fmt.Println("NA")
			} else {
				stack := make([]int, 0)
				V := d
				for V != c {
					stack = append(stack, V)
					V = rev[V]
				}
				fmt.Print(num[c])
				for len(stack) > 0 {
					fmt.Printf(" %d", num[stack[len(stack)-1]])
					stack = stack[:len(stack)-1]
				}
				fmt.Println()
			}
		}
	}
}

C++: #include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <cmath>
using namespace std;

#define MAX 1100
#define INF (1<<29)
#define EPS 1e-9

struct Point{
  int x, y, id;
};

vector<Point> bill;
double dist[MAX][MAX];

int V;

void init(){
  bill.clear();
  for(int i = 0 ; i < MAX ; i++){
    for(int j = 0 ; j < MAX ; j++){
      dist[i][j] = INF;
      if(i == j) dist[i][j] = 0;
    }
  }
}

int prev[MAX];
void dijkstra(int s){
  int d[MAX];
  bool used[MAX];
  for(int i = 0 ; i < MAX ; i++){
    d[i] = INF;
    used[i] = false;
    prev[i] = -1;
  }
  //fill(d, d+MAX, INF);
  //fill(used, used+MAX, false);
  //fill(prev, prev+MAX, -1);
  d[s] = 0;
  
  while(true){
    int v = -1;
    for(int u = 0 ; u < V ; u++){
      if(!used[u] && (v == -1 || d[u] < d[v])) v = u;
    }
    if(v == -1) break;
    used[v] = true;
    
    for(int u = 0 ; u < V ; u++){
      if(d[u] > d[v] + dist[v][u]){
	d[u] = d[v] + dist[v][u];
	prev[u] = v;
      }
    }
  }
}

vector<int> get_path(int t){
  vector<int> path;
  for(; t != -1 ; t = prev[t]) path.push_back(t);
  reverse(path.begin(), path.end());
  return path;
}

double getDist(int from, int to){
  double ret = sqrt( 1.0 * ( ((bill[from].x - bill[to].x)*(bill[from].x - bill[to].x)) +
			     ((bill[from].y - bill[to].y)*(bill[from].y - bill[to].y)) ) );
  return ret;
}
  
int main(){
  while(cin >> V, V){
    init();
    Point p;
    for(int i = 0 ; i < V ; i++){
      cin >> p.id >> p.x >> p.y;
      p.id--;
      bill.push_back(p);
    }
    
    for(int i = 0 ; i < V ; i++){
      for(int j= i+1 ; j < V ; j++){
	double dis = getDist(bill[i].id, bill[j].id);
	//if(dis >= 50 + EPS) continue;
	if(dis <= 50 + EPS){
	dist[bill[i].id][bill[j].id] = dist[bill[j].id][bill[i].id] = dis;
	}
      }
    }
    int m;    
    cin >> m;
    int s, g;
    while(m--){
      cin >> s >> g;
      s--, g--;
      dijkstra(s);
      vector<int> ans_path;
      ans_path = get_path(g);
      if(ans_path.size() == 1) cout << "NA" << endl;
      else{
	for(int i = 0 ; i < (int)ans_path.size() ; i++){
	  if(i == (int)ans_path.size()-1) cout << ans_path[i]+1 << endl;
	  else cout << ans_path[i]+1 << ' ';
	}
      }
    } 
  }
  return 0;
}

C++: #include<iostream>
#include<cstring>
#include<set>
#include<cmath>

double adjacive[1000][1000];
int field[1000][1000];
int prev[1000];
std::set<int> building;

int input();
void dijkstra(int start);
void output(int start,int goal);

int main()
{
	while(1)
	{
		int n;
		n=input();
		if(n==0)break;
		
		int m;
		std::cin>>m;
		for(int i=0;i<m;i++)
		{
			int bs,bg;
			std::cin>>bs>>bg;
			dijkstra(bs);
			output(bs,bg);
		}
	}
	return 0;
}

int input()
{
	int n;
	std::cin>>n;
	if(n==0)return 0;
	memset(field,0,sizeof(field));
	building.clear();

	for(int i=0;i<1000;i++){for(int j=0;j<1000;j++){adjacive[i][j]=1.0e+10;}}

	for(int i=0;i<n;i++)
	{
		int b,x,y;
		std::cin>>b>>x>>y;
		field[y][x]=b;
		building.insert(b);
	}
	for(int y=0;y<1000;y++)
	{
		for(int x=0;x<1000;x++)
		{
			if(field[y][x]!=0)
			{
				for(int i=-50;i<=50;i++)
				{
					for(int j=-50;j<=50;j++)
					{
						if(i+y>=0&&i+y<1000&&j+x>=0&&j+x<1000&&field[i+y][j+x]!=0&&i*i+j*j<=2500)
						{
							adjacive[field[y][x]-1][field[y+i][x+j]-1]=hypot(i,j);
						}
					}
				}
			}
		}
	}
	return n;
}

void dijkstra(int start)
{
	bool visited[1000];
	double cost[1000];
	memset(visited,0,sizeof(visited));
	memset(prev,-1,sizeof(prev));

	for(int i=0;i<1000;i++){cost[i]=1.0e+10;}
	
	cost[start-1]=0;
	while(1)
	{
		int u=-1;
		for(std::set<int>::iterator it=building.begin();it!=building.end();it++)
		{
			if(!visited[*it-1]&&(u==-1||cost[*it-1]<cost[u]))
			{
				u=*it-1;
			}
		}
		if(u==-1)break;
		visited[u]=true;
		for(std::set<int>::iterator it=building.begin();it!=building.end();it++)
		{
			if(cost[*it-1]>cost[u]+adjacive[u][*it-1])
			{
				cost[*it-1]=cost[u]+adjacive[u][*it-1];
				prev[*it-1]=u;
				
			}
		}
	}
}

void output(int start,int goal)
{
	int temp[1000];
	int b=goal-1;
	int i=0;
	bool isNA=true;

	while(prev[b]!=-1)
	{
		temp[i]=b+1;
		i++;
		b=prev[b];
		isNA=false;
	}
	if(start==goal)
	{
		std::cout<<start<<std::endl;
	}
	if(isNA)
	{
		std::cout<<"NA"<<std::endl;
	}
	else
	{
		std::cout<<start;
		for(i=i-1;i>=0;i--)
		{
			std::cout<<' '<<temp[i];
		}
		std::cout<<std::endl;
	}
}