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 <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;
	double cost;
};

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

const int MAX_V = 5000;

vector<edge> G[MAX_V];
double 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] = 0.0;
	que.push(P(0.0,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==6){
//				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=sqrt((double)dist);
					e.to=vb[j].node;
					G[vb[i].node].push_back(e);

					//e.cost=dist;
					e.to=vb[i].node;
					G[vb[j].node].push_back(e);
				}
			}
		}

		//dijkstra(1);
		//cout<<d[22]<<endl;

		int m;
		cin>>m;
		for(int i = 0; i < m; i++){
			int s,g;
			cin>>s>>g;
			dijkstra(s);
			if(EQ(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;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
#include <cstring>
#include <cmath>
#include <cstdio>

#define INF 1 << 28
#define EPS 1e-5

using namespace std;

typedef double Weight; 

struct Edge{
    int src;
    int dst;
    Weight weight;

    Edge(int src, int dst, Weight weight):
        src(src), dst(dst), weight(weight){ }
};

struct Node{
    int index;
    int cost;
    int prev;

    Node(int index, int cost, int prev) :
        index(index), cost(cost), prev(prev){ }
};

bool operator <(const Node &a, const Node &b){
    if(a.cost == b.cost){
        return a.index > b.index;
    }else{
        return a.cost > b.cost;
    }
}

void dijkstra(int s, vector<int> &costs, vector<int> &prev, vector<vector<Edge> > &edges){
    int n=costs.size();
    bool picked[n];
    priority_queue<Node> q;

    costs.assign(n,INF);
    prev.assign(n,-1);
    costs[s] = 0;
    memset(picked, false, sizeof(picked));
    q.push(Node(0,0,-2));

    while(!q.empty()){
        Node fix = q.top(); 
        q.pop();
        if(prev[fix.index] != -1) continue;
       
        picked[fix.index] = true;
        costs[fix.index] = fix.cost;

        prev[fix.index] = fix.prev;

        for(int i=0;i<edges[fix.index].size();i++){ //foreach edge from fixed
            if(costs[edges[fix.index][i].dst] > costs[fix.index] + edges[fix.index][i].weight){
                q.push(Node(edges[fix.index][i].dst, edges[fix.index][i].weight + costs[fix.index], fix.index));
            }
        }
    }
}

vector<int> createpath(vector<int> &prev, int e){
    vector<int> ret;
    int pos = e;
    while(1){
        ret.push_back(pos);
        pos = prev[pos];
        if(pos == -2){
            reverse(ret.begin(),ret.end());
            return ret;
        }
    }
}

struct building{
    int index;
    int x;
    int y;
    
    building(int index, int x, int y):
        index(index), x(x), y(y){}
};

int main(){
    int n;
    while(cin >> n && n){
        vector<vector<Edge> > edges(n);
        vector<int> cost(n);
        vector<int> prev(n);
        vector<int> name(n);
        vector<building> b;
        vector<int> ans;
        double dist;
        int m;
        int src,dst;
        int index,x,y;

        for(int i=0;i<n;i++){
            cin >> name[i] >> x >> y;
            b.push_back(building(i,x,y));
        }

        for(int i=0;i<n;i++){
            for(int j=i+1;j<n;j++){
                dist = sqrt(pow(b[i].x - b[j].x,2) + pow(b[i].y - b[j].y, 2));
                if(dist <= 50+EPS){
                    edges[i].push_back(Edge(i,j,dist));
                    edges[j].push_back(Edge(j,i,dist));
                }
            }
        }
        
        cin >> m;
        for(int i=0;i<m;i++){
            int srcname,dstname;
            cin >> srcname >> dstname;
            for(int i=0;i<n;i++){
                if(name[i] == srcname){
                    src = i;
                }
                if(name[i] == dstname){
                    dst = i;
                }
            }
            dijkstra(src, cost, prev, edges);
            if(cost[dst] == INF){
                cout << "NA" << endl;
            }else{
                ans = createpath(prev,dst);
                for(int j=0;j<ans.size()-1;j++){
                    cout << name[ans[j]] << " ";
                }
                cout << name[ans.back()] << endl;
            }
        }
    }
}