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 <bits/stdc++.h>
using namespace std;

struct Edge {
  int src, dst, w;
};

typedef vector<vector<Edge> > Graph;
typedef pair<int,int> Pair;

const int INF = 1<<28;

vector<int> dijkstra(int src, int dst, const Graph &g) {
  int n = g.size();
  priority_queue< Pair,vector<Pair>,greater<Pair> > que;
  vector<int> cost(n, INF), 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,cost});
          g[j].push_back((Edge){j,i,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;
}

C++: #include <stdio.h>
#include <iostream>
#include <vector>
#include <list>
#include <cmath>
#include <fstream>
#include <algorithm>
#include <string>
#include <queue>
#include <set>
#include <map>
#include <complex>
#include <iterator>
#include <cstdlib>
#include <sstream>

using namespace std;

#define EPS (1e-10)
#define EQ(a,b) (abs((a) - (b)) < EPS)
#define EQV(a,b) (EQ((a).real(),(b).real()) && EQ((a).imag(),(b).imag()))

typedef long long ll;

const int MAX_SIZE = 10000;

struct edge{
	int to;
	int cost;
};

typedef pair<int,int> P;
int V;

const int MAX_V = 5000;

vector<edge> G[MAX_V];
int d[MAX_V];
const int INF = 1000000000;

int prevv[MAX_V];

void dijkstra(int s){
	priority_queue<P,vector<P>,greater<P> > que;
	fill(d,d+MAX_V,INF);
	fill(prevv,prevv+MAX_V,-1);
	d[s] = 0;
	que.push(P(0,s));
	while(!que.empty()){
		P p = que.top();
		que.pop();
		int v = p.second;
		if(d[v] < p.first)
			continue;
		for(int i = 0; i < G[v].size(); i++){
			//if(v==11){
			//	cout<<endl;
			//}
			edge e = G[v][i];
			if(d[e.to] > d[v] + e.cost){
				d[e.to] = d[v] + e.cost;
				que.push(P(d[e.to],e.to));
				// »Ìm[hÖÌÅZ£oHðL^µÄ¨­
				prevv[e.to] = v;
			}
		}
	}
}

class Building{
public:
	int node;
	int x;
	int y;
};


int main(){

	int n;
	while(cin>>n&&n!=0){
		vector<Building> vb;
		for(int i = 0; i < n; i++){
			Building b;
			cin>>b.node>>b.x>>b.y;
			vb.push_back(b);
		}
		// »ê¼êÌgÝí¹ÉÎµÄµç×é
		for(int i = 0; i < vb.size(); i++){
			for(int j = i+1; j < vb.size(); j++){
				int dist = (vb[i].x-vb[j].x)*(vb[i].x-vb[j].x)+(vb[i].y-vb[j].y)*(vb[i].y-vb[j].y);
				// rÔÌ£Ìñæª2500Èº¾Á½êAGbWðÞ·Ô
				if(dist<=2500){
					edge e;
					e.cost=dist;
					e.to=vb[j].node;
					G[vb[i].node].push_back(e);
					e.to=vb[i].node;
					G[vb[j].node].push_back(e);
				}
			}
		}
		
		int m;
		cin>>m;
		for(int i = 0; i < m; i++){
			int s,g;
			cin>>s>>g;
			dijkstra(s);
			//cout<<d[g]<<endl;
			if(d[g]==INF)
				cout<<"NA"<<endl;
			else{
				//cout<<d[g]<<endl;
				vector<int> path;
				path.push_back(g);
				int cp=g;
				while(1){
					int np=prevv[cp];
					cp=np;
					path.push_back(cp);
					if(cp==s)
						break;
				}
				for(int j = 0; j < path.size(); j++){
					cout<<path[path.size()-1-j];
					if(j==path.size()-1)
						cout<<endl;
					else
						cout<<" ";
				}
			}
		}
		for(int i = 0; i < MAX_V; i++)
			G[i].clear();
	}

	return 0;
}