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 1010
#define INF (1<<29)
#define EPS 1e-9

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

vector<Point> bill;
double dist[MAX][MAX];
int prev[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;
    }
  }
}

void dijkstra(int s){
  int d[MAX];
  bool used[MAX];
  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;
}

inline double getDist(int from, int to){
  double ret = sqrt( ((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 ; j < V ; j++){
	double dis = getDist(bill[i].id, bill[j].id);
	if(dis > 50 + EPS) continue;
	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 = 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 <cstdio>
#include <iostream>
#include <vector>
#include <stack>
#include <queue>
#include <string>
#include <map>
#include <algorithm>
#include <cmath>
#define rep(i,n) for(int i=0; i<n; ++i)
using namespace std;
typedef pair<int,int> P;

const double INF = 10000000;
struct Node{
  int x,y;
  vector<int> to;
  vector<double> cost;
  vector<int> root;
};
int N,M;
int V;
Node G[1001];
int d[1001];
bool visit[1001];

inline double dist(Node a, Node b){
  return sqrt((double)((a.x-b.x)*(a.x-b.x) + (a.y-b.y)*(a.y-b.y)));
}

void init(){
  for(int i=1; i<=1001; ++i){
    G[i-1].root.clear();
    d[i-1] = INF;
    visit[i-1] = false;
  }
}
void makeEdge(){
  for(int i=1; i<=N; ++i){
    G[i].to.clear();
    G[i].cost.clear();
    for(int j=1; j<=N; ++j){
      if(i == j) continue;
      if(dist(G[i],G[j]) <= 50){
//        printf("%d -> %d dist::%d \n",i,j,dist(G[i],G[j]));
        G[i].to.push_back(j);
        G[i].cost.push_back(dist(G[i],G[j]));
      }
    }
//    printf("%d\n",G[i].to.size());
  }
}

void dijkstra(int e){
  int cnt = 1;
  while(cnt <= N){
    double m = INF;
    vector<int> m_r;
//    printf("cnt:%d\n",cnt);
    for(int i=1; i<=N; ++i){
      if(visit[i] == false) continue;
      for(int j=0;j<G[i].to.size();++j){
        if(visit[G[i].to[j]] == true) continue;
//        printf("%d->%d\n",i,G[i].to[j]);
        if(d[i] + G[i].cost[j] < m){
          m = d[i] + G[i].cost[j];
          m_r.assign(G[i].root.begin(), G[i].root.end());;
          m_r.push_back(G[i].to[j]);
          
        }
      }
    }
    if(m == INF) break;
    G[m_r.back()].root.assign(m_r.begin(), m_r.end());
    d[m_r.back()] = m;
    visit[m_r.back()] = true;
//    printf("%d  (cost:%lf)\n",m_r.back(),m);

    if(m_r.back() == e){
      cout << G[m_r.back()].root[0];
      for(int i=1; i<G[m_r.back()].root.size(); ++i){
        cout << " " << G[m_r.back()].root[i];
      }
      cout << endl;
      return;
    }
    cnt++;
  }
  cout << "NA " << endl;
  return;
}

int main(){
  while(cin >> N && N){
    for(int i=1; i<=N; ++i){
      int id;
      cin >> id;
      cin >> G[id].x >> G[id].y;
    }
    makeEdge();
    
    cin >> M;
    
    for(int i=1; i<=M; ++i){
      init();
      int s,e;
      cin >> s >> e;
      visit[s] = true;
      d[s] = 0;
      G[s].root.push_back(s);
      dijkstra(e);
    }
    
  }
  return 0;
}

C++: #include<iostream>
#include<cmath>
#include<vector>
#include<algorithm>
#define INF 100000

using namespace std;

void dijkstra(int);
vector<int>get_path(int);

int V,prev[1001];
double cost[1001][1001],d[1001];
bool used[1001];

int main(void){

  int b[1001],m,s,g;
  double x[1001],y[1001];

  while(cin >> V,V){
    for(int i=0;i<V;i++)
      cin >> b[i] >> x[i] >> y[i];
    
    for(int i=0;i<=V;i++)
      for(int j=0;j<=V;j++)
	cost[i][j]=INF;

    for(int i=0;i<V;i++){
      for(int j=0;j<V;j++){
	if(i!=j){
	  double a=sqrt(pow(x[i]-x[j],2)+pow(y[i]-y[j],2));
	  if(50.>=a)cost[b[i]][b[j]]=cost[b[j]][b[i]]=a;
	}
      }
    }
    
    cin >> m;
    for(int i=0;i<m;i++){
      cin>> s >> g;
      
	dijkstra(s);

	if(used[g]){

	  vector<int>p=get_path(g);

	  for(int j=0;j<p.size();j++){
	    cout << p[j];

	    if(j<p.size()-1)cout <<" ";
	    else cout << endl;
	  }
	}
	else cout << "NA" << endl; 
    }
  }
  
  return 0;
}

void dijkstra(int s){
  fill(d,d+V+1,INF);
  fill(used,used+V+1,false);
  fill(prev,prev+V+1,-1);
  d[s]=0;

  while(true){
    int v=-1;
    for(int u=1;u<=V;u++){
      if(!used[u]&&(v==-1||d[u]<d[v]))v=u;
    }

    if(v==-1 || d[v]==INF)break;
    used[v]=true;

    for(int u=1;u<=V;u++){
      if(d[u]>d[v]+cost[v][u]){
	d[u]=d[v]+cost[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;
}