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 <vector>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <sstream>
using namespace std;

typedef vector< vector< double > > Array2D;
typedef vector< double > Array1D;

const double EPS = 10e-9;
const int SIZE = 1001;

class Building
{
public:
	Building( int _id, int _x, int _y ) : id( _id ), x( _x ), y( _y ){}
	double distance( const Building& b ) const
	{
		int x = this->x - b.x;
		int y = this->y - b.y;
		return sqrt( static_cast<double>( x * x + y + y ) );
	}

	bool operator<( const Building& b ) const
	{
		if( this->x < b.x ) return true;
		if( this->x > b.x ) return false;
		if( this->y < b.y ) return true;
		if( this->y > b.y ) return false;
		return this->id < b.id;
	}

	int id;
	int x;
	int y;
};

class Path
{
public:
	Path( int _now, double _cost, vector< int > _root ) : now( _now ), cost( _cost )
	{
		_root.push_back( now );
		root = _root;
	}
	Path next( int n, double cost ) const
	{
		Path ret = *this;
		ret.now = n;
		ret.cost += cost;
		ret.root.push_back( n );
		return ret;
	}
	bool operator<( const Path& p ) const
	{
		return this->cost < p.cost;
	}
	int now;
	double cost;
	vector< int > root;
};

void sortBuildingXY( vector< Building >* const pb )
{
	sort( pb->begin(), pb->end() );
}

void measure( vector< Building >& list, Array2D& d, int index )
{
	Building& o = list[ index ];
	for( int i = index + 1; i < list.size(); ++i ){
		Building& a = list[ i ];
		if( a.x - o.x > 50 ){
			break;
		}
		if( a.y - o.y > 50 ){
			continue;
		}
		double dis = o.distance( a );
		if( 50.0 - dis >= EPS ){
			d[ o.id ][ a.id ] = d[ a.id ][ o.id ] = dis;
		}
	}
}

string answear( Path& p )
{
	string ret;
	bool first = true;
	int size = p.root.size();
	for( int i = 0; i < size; ++i ){
		if( first ){
			first = false;
		}else{
			ret += ' ';
		}
		ostringstream ss;
		ss << p.root[ i ];
		string s;
		s = ss.str();
		ret += s;
	}
	return ret;
}

string solve( vector< Building >& list, Array2D& d, bool* past, int s, int g, int n )
{
	vector< Path > vec;
	Path start( s, 0.0, vector< int >() );
	for( int i = 0; i <= n; ++i ){
		if( d[ s ][ i ] > 0.0 ){
			vec.push_back( start.next( i, d[ s ][ i ] ) );
		}
	}
	past[ s ] = true;

	while( !vec.empty() ){
		sort( vec.begin(), vec.end() );
		vector< Path >::iterator itr = vec.begin();
		while( itr != vec.end() && past[ itr->now ] ){
			itr = vec.erase( itr );
		}
		if( vec.empty() ){
			return string( "NA" );
		}
		Path path = *itr;
		vec.erase( itr );
		int t = path.now;
		if( t == g ){
			return answear( path );
		}
		past[ t ] = true;
		for( int i = 0; i <= n; ++i ){
			if( !past[ i ] && d[ t ][ i ] > 0.0 ){
				vec.push_back( path.next( i, d[ t ][ i ] ) );
			}
		}
	}
	return string( "NA" );
}

int main()
{
	Array1D tmpArray;
	for( int i = 0; i < SIZE; ++i ){
		tmpArray.push_back( 0.0 );
	}

	int n;
	while( cin >> n && n ){
		Array2D distance;
		for( int i = 0; i < SIZE; ++i ){
			distance.push_back( tmpArray );
		}
		vector< Building > BuildingList;
		for( int i = 0; i < n; ++i ){
			int id, x, y;
			cin >> id >> x >> y;
			BuildingList.push_back( Building( id, x, y ) );
		}
		sortBuildingXY( &BuildingList );

		for( int i = 0; i < n; ++i ){
			measure( BuildingList, distance, i );
		}

		int m;
		cin >> m;
		for( int i = 0; i < m; ++i ){
			int s, g;
			bool past[ SIZE ];
			memset( past, 0, sizeof(past) );

			cin >> s >> g;
			cout << solve( BuildingList, distance, past, s, g, n ) << endl;
		}
	}
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
 
struct Edge {
  int src, dst;
  double w;
};
 
typedef vector<vector<Edge> > Graph;
typedef pair<double,int> Pair;
 
const double inf = 1e20;
 
vector<int> dijkstra(int src, int dst, const Graph &g) {
  int n = g.size();
  priority_queue< Pair,vector<Pair>,greater<Pair> > que;
  vector<double> cost(n, inf);
  vector<int> prev(n);
  cost[src] = 0;
  que.push(Pair(0, src));
  while(que.size()) {
    const Pair s = que.top();
    que.pop();
    if(cost[s.second] < s.first) continue;
    if(s.second == dst) {
      vector<int> path;
      int p = dst;
      while(1) {
        path.push_back(p);
        if(p == src) break;
        p = prev[p];
      }
      reverse(path.begin(), path.end());
      return path;
    }
    for(int i = 0; i < g[s.second].size(); ++i) {
      const Edge &e = g[s.second][i];
      Pair t(s.first + e.w, e.dst);
      if(cost[t.second] <= t.first) continue;
      que.push(t);
      cost[t.second] = t.first;
      prev[t.second] = s.second;
    }
  }
  return vector<int>();
}
 
int main() {
  int n;
  while(cin >> n && n) {
    map<int,int> id, rid;
    vector<int> x(n), y(n);
    for(int i = 0; i < n; ++i) {
      int b;
      cin >> b >> x[i] >> y[i];
      id[b] = i;
      rid[i] = b;
    }
    Graph g(n);
    for(int i = 0; i < n; ++i) {
      for(int j = i+1; j < n; ++j) {
        int cost = (x[i]-x[j])*(x[i]-x[j]) + (y[i]-y[j])*(y[i]-y[j]);
        if(cost <= 50*50) {
          g[i].push_back((Edge){i,j,sqrt(cost)});
          g[j].push_back((Edge){j,i,sqrt(cost)});
        }
      }
    }
    int m;
    cin >> m;
    while(m--) {
      int src, dst;
      cin >> src >> dst;
      vector<int> v = dijkstra(id[src], id[dst], g);
      if(v.empty()) {
        cout << "NA" << endl;
      } else {
        for(int i = 0; i < v.size(); ++i) {
          if(i) cout << " ";
          cout << rid[v[i]];
        }
        cout << endl;
      }
    }
  }
  return 0;
}