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 <algorithm>
#include <map>
#include <vector>
#include <iostream>
#include <sstream>
#include <cstdio>
#include <cstring>
#include <cctype>
#include <cstdlib>
#include <cmath>
#include <string>
#include <queue>
#include <stack>
#include <set>
using namespace std;

#define REP(i,n) for(int i=0; i<n; ++i)
#define IREP(it,array) for(vector<int>::iterator it=array.begin(); it!=array.end(); ++it)
#define PREP(it,array) for(vector<P>::iterator it=array.begin(); it!=array.end(); ++it)
#define SREP(it,array) for(vector<string>::iterator it=array.begin(); it!=array.end(); ++it)

#define MP       make_pair
#define PB       push_back
#define ALL(x)   (x).begin(),(x).end()

const int INF = 1<<29;
const double EPS = 1e-9;
double zero(double d){
  return d < EPS ? 0.0 : d;
}

typedef long long LL;
typedef pair<double,int> P;

int main()
{
  cout.setf(ios::fixed, ios::floatfield);
  cout.precision(7);

  int n;
  while(cin>>n,n){
    pair<int,P> build[n];
    REP(i,n){
      int b,x,y;
      cin>>b>>x>>y;
      build[i].first = b;
      build[i].second.first = x;
      build[i].second.second = y;
    }

    double d[n+1][n+1];
    REP(i,n+1){
      fill( d[i], d[i]+n+1, INF );
    }
    d[0][0] = 0;
    REP(i,n){
      REP(j,n){
	P from = build[i].second;
	P to = build[j].second;
	double cost = sqrt(pow((double)from.first-to.first,2) +
			   pow((double)from.second-to.second,2));
	if(cost <= 50 ){
	  d[build[i].first][build[j].first] = 
	    d[build[j].first][build[i].first] = cost;
	}
      }
      d[i+1][i+1] = 0;
    }
    /*
    cout << "::" << d[20][18] << endl;
    cout << "::" << d[18][19] << endl;
    cout << "::" << d[19][6] << endl;

    cout << ":::" << d[20][11] << endl;
    cout << ":::" << d[11][6] << endl;
    */
    //    cout << n << endl;

    int m;
    cin>>m;
    REP(_t,m){
      int s,g;
      cin>>s>>g;
      
      priority_queue<P,vector<P>,greater<P> > que;
      double dis[n+1];
      fill( dis, dis+n+1, INF );
      int back[n+1];
      fill( back, back+n+1, INF );
      dis[s] = 0;
      que.push( P(0,s) );

      while( ! que.empty() ){
	P e = que.top(); que.pop();

	if( e.first > dis[e.second] )
	  continue;
	//	dis[e.second] = e.first;

	/*	if( e.second == g ){
	  cout << "end:" << e.second << endl;
	  break;
	  }*/

	REP(i,n+1){
	  if( dis[i] > dis[e.second] + d[e.second][i] ){
	    dis[i] = dis[e.second] + d[e.second][i];
	    que.push( P(dis[i],i) );
	    back[i] = e.second;
	  }
	}
      }

      if(dis[g]==INF){
	cout << "NA" << endl;
	continue;
      }

      vector<int> res;
      res.PB(g);

      int i=g;
      while(back[i]!=INF){
	res.PB(back[i]);
	i=back[i];
      }

      reverse(ALL(res));
      REP(i,res.size()){
	if(i!=0)
	  cout << " ";
	cout << res[i];
      }
      cout << endl;

    }
  }

  return 0;
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <cmath>
#include <algorithm>
#include <queue>
#include <functional>
#include <utility>
#include <unordered_map>
#include <map>

#define INF 2147483647
#define INF_LL 9223372036854775807
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;

struct pos { int x, y; };
int main() {
	while (1) {
		int n;
		cin >> n;
		if (n == 0)break;
		vector<pos> building(n);
		vector<vector<double> > cost(n, vector<double>(n, 0));
		for (int i = 0; i < n; i++) {
			int b;
			cin >> b; b--;
			cin >> building[b].x >> building[b].y;
		}
		for (int i = 0; i < n; i++)for (int j = 0; j < n; j++) {
			if (i == j)cost[i][j] = 0;
			else cost[i][j] = sqrt(pow(building[i].x - building[j].x, 2) + pow(building[i].y - building[j].y, 2));
			if (cost[i][j] > 50)cost[i][j] = INF_LL;
		}

		int m;
		cin >> m;
		for (int i = 0; i < m; i++) {
			int s, g, c;
			cin >> s >> g;
			s--; g--;
			c = g;
			vector<double> d(n, INF);
			vector<bool> used(n, false);
			vector<int> prev(n, -1);
			vector<int> path;
			d[s] = 0;
			while (1) {
				int v = -1;
				for (int u = 0; u < n; u++) {
					if (!used[u] && (v == -1 || d[u] < d[v])) v = u;
				}
				if (v == -1)break;
				used[v] = true;
				for (int u = 0; u < n; u++) {
					if (d[u] > d[v] + cost[v][u]) {
						d[u] = d[v] + cost[v][u];
						prev[u] = v;
					}
				}
			}
			for (; g != -1; g = prev[g]) path.push_back(g);
			reverse(path.begin(), path.end());
			if (path[0] == c && s != c)cout << "NA" << endl;
			else {
				for (int i = 0; i < path.size(); i++) {
					cout << path[i] + 1;
					if (i != path.size() - 1) cout << " ";
				}
				cout << endl;
			}
		}
	}


	return 0;
}