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 <cmath>
#include <cstring>
#include <memory>
#include <map>

using namespace std;

#define REP(i, n)           for(int(i)=0;(i)<(n);++(i))
#define FILL(m,v)           memset(m, v, sizeof(m))

int b[1001], x[1001], y[1001];
double wf[1001][1001];
int rt[1001][1001];

const double inf = 1e12;
map<int,int> id, rid;

void trace(int s, int g){
    int r = rt[s][g];
    if(g == r){
        cout << " " << id[g];
        return;
    }
    trace(s,r);
    trace(r,g);
}

int main(){
    int n, m;
    while(cin >> n && n){
        FILL(x, 0);
        FILL(y, 0);
        FILL(rt, 0);
        REP(i,1001) REP(j,1001) wf[i][j] = inf;
        REP(i,n){
            cin >> b[i] >> x[i] >> y[i];
            id[i] = b[i];
            rid[b[i]] = i;
        }
        REP(i,n) REP(j,n){
            if(i == j){
                wf[i][j] = 0;
                continue;
            }
            int dist = (x[i]-x[j])*(x[i]-x[j])+(y[i]-y[j])*(y[i]-y[j]);
            if(dist <= 50*50){
                wf[i][j] = sqrt((double)dist);
                rt[i][j] = j;
            }
        }
        REP(k,n) REP(i,n) REP(j,n) {
            if(wf[i][j] > wf[i][k] + wf[k][j]){
                wf[i][j] = wf[i][k] + wf[k][j];
                rt[i][j] = k;
            }
        }

        cin >> m;
        int s,g;
        REP(i,m){
            cin >> s >> g;
            s = rid[s], g = rid[g];
            if(wf[s][g] == inf){
                cout << "NA" << endl;
                continue;
            }
            cout << id[s]; trace(s,g); cout << endl;
        }
    }
    return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

#define MAX 1000
#define INF 1e9

int V;
struct State{
  int x, y;
};

vector<State> vec;

double check(State a, State b){
  return sqrt(pow((a.x-b.x),2.) + pow(a.y-b.y,2.));
}

double dist[MAX];
bool used[MAX];
int prev[MAX];
double cost[MAX][MAX];

void dijkstra(int s, int t){
  fill(dist, dist+MAX, INF);
  memset(used,false,sizeof(used));
  memset(prev,-1,sizeof(prev));
  dist[s] = 0;

  while(true){
    int v = -1;
    for(int u = 0 ; u < V ; u++){
      if(!used[u] && (v == -1 || 
		      dist[u] < dist[v])){
	v = u;
      }
    }

    if(v == -1){
      break;
    }else{
      used[v] = true;
    }

    for(int u = 0 ; u < V ; u++){
      if(dist[u] > dist[v] + cost[u][v] && cost[u][v] <= 50){
	dist[u] = dist[v] + cost[u][v];
	prev[u] = v;
      }
    }
  }

  if(dist[t] == INF){
    cout << "NA" << endl;
  }else{
    vector<int> path;
    for(int i = t ; i != -1 ; i = prev[i]){
      path.push_back(i);
    }
    reverse(path.begin(), path.end());
    
    int len = path.size();
    for(int i = 0 ; i < len ; i++){
      cout << path[i]+1 << (i == len-1 ? '\n' : ' ');
    }
  }
}

int main(){
  int n, start, goal, num;
  State s;

  while(cin >> V, V){
    State distance[MAX];

    vec.clear();
    fill(cost[0],cost[V],INF);
    for(int i = 0 ; i < V ; i++){
      cin >> num >> s.x >> s.y;
      vec.push_back(s);
      distance[num-1] = s;
    }

    for(int i = 0 ; i < V-1 ; i++){
      for(int j = i+1 ; j < V ; j++){
	cost[i][j] = cost[j][i] = 
	  check(distance[i],distance[j]);
      }
    }
 
    cin >> n;
    for(int i = 0 ; i < n ; i++){
      cin >> start >> goal;
      start--, goal--;
      dijkstra(start, goal);
    }
  }
  
  return 0;
}