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;

#define dump(n) cout<<"# "<<#n<<'='<<(n)<<endl
#define repi(i,a,b) for(int i=int(a);i<int(b);i++)
#define peri(i,a,b) for(int i=int(b);i-->int(a);)
#define rep(i,n) repi(i,0,n)
#define per(i,n) peri(i,0,n)
#define all(c) begin(c),end(c)
#define mp make_pair
#define mt make_tuple

typedef unsigned int uint;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef vector<string> vs;

const int INF=1e9;
const int MOD=1e9+7;
const double EPS=1e-9;

template<typename T1,typename T2>
ostream& operator<<(ostream& os,const pair<T1,T2>& p){
	return os<<'('<<p.first<<','<<p.second<<')';
}
template<typename T>
ostream& operator<<(ostream& os,const vector<T>& a){
	os<<'[';
	rep(i,a.size()) os<<(i?" ":"")<<a[i];
	return os<<']';
}

struct Edge{
	int src,dst;
	double weight;
	Edge(){}
	Edge(int s,int d,double w):src(s),dst(d),weight(w){}
};
typedef vector<vector<Edge>> Graph;
bool operator<(const Edge& a,const Edge& b){return a.weight<b.weight;}
bool operator>(const Edge& a,const Edge& b){return a.weight>b.weight;}

void Dijkstra(const Graph& g,int v,vd& dist,vi& prev)
{
	priority_queue<Edge,vector<Edge>,greater<Edge>> pq;
	pq.emplace(-1,v,0);
	while(pq.size()){
		Edge cur=pq.top(); pq.pop();
		if(dist[cur.dst]!=INF) continue;
		dist[cur.dst]=cur.weight;
		prev[cur.dst]=cur.src;
		for(Edge e:g[cur.dst])
			pq.emplace(e.src,e.dst,cur.weight+e.weight);
	}
}
void BuildPath(const vi& prev,int v,vi& path)
{
	for(int u=v;u!=-1;u=prev[u])
		path.push_back(u);
	reverse(all(path));
}

int main()
{
	for(int n;cin>>n && n;){
		vi bs(n),xs(n),ys(n);
		rep(i,n) cin>>bs[i]>>xs[i]>>ys[i];
		
		map<int,int> f;
		rep(i,n) f[bs[i]]=i;
		
		Graph g(n);
		rep(i,n) rep(j,n){
			int dx=xs[j]-xs[i],dy=ys[j]-ys[i];
			if(dx*dx+dy*dy<=50*50){
				double d=sqrt(dx*dx+dy*dy);
				g[i].emplace_back(i,j,d);
			}
		}
		
		vvd dists(n,vd(n,INF));
		vvi prevs(n,vi(n,-1));
		rep(i,n) Dijkstra(g,i,dists[i],prevs[i]);
		
		int m; cin>>m;
		rep(i,m){
			int u,v; cin>>u>>v; u=f[u],v=f[v];
			if(dists[u][v]==INF){
				cout<<"NA"<<endl;
				continue;
			}
			vi path; BuildPath(prevs[u],v,path);
			rep(i,path.size())
				cout<<(i?" ":"")<<bs[path[i]];
			cout<<endl;
		}
	}
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <cstring>
#include <complex>

using namespace std;

const int MAX_V = 1001;
// d[u][v]Íu©çvÖÌRXgBßÉ×Ú·éGbWÌRXgðüêÄ¨¢½è·êÎæ¢Í¸B
double d[MAX_V][MAX_V];
const int INF=1000000000;
// ¸_
int V;

#define EPS (1e-10)
#define EQ(a,b) (abs((a)-(b))<EPS)

// prv[i][j] -> iªX^[gn_ÌÆ«Aj©çÇ±Éßé©
int prv[MAX_V][MAX_V];

// S_ÎÅZoHâèðÆ­O(V^3)AÓª ÁÄà®ì
void warshall_floyd(){
    for(int i = 0; i < V; i++){
        for(int j = 0; j < V; j++){
            for(int k = 0; k < V; k++){
                //d[j][k]=min(d[j][k],d[j][i]+d[i][k]);
                if(d[j][k]>d[j][i]+d[i][k]){
                    int cp=k;
                    // XV
                    while(1){
                        prv[j][cp]=prv[i][cp];
                        cp=prv[i][cp];
                        if(cp==i)break;
                    }
                    d[j][k]=d[j][i]+d[i][k];
                }
            }
        }
    }
}
typedef complex<double> P;

void init(int n){
    V=n;
    for(int i = 0; i < MAX_V; i++){
        for(int j = 0; j < MAX_V; j++){
            if(i==j)d[i][j]=0;
            else d[i][j]=INF;
            prv[i][j]=INF;
        }
    }
}

int main(){
    int n;
    while(cin>>n&&n!=0){
        init(n);
        int billNum[MAX_V];
        P billP[MAX_V];
        for(int i=0;i<n;i++){
            int x,y;
            cin>>billNum[i]>>x>>y;
            billP[i]=P(x,y);
            billNum[i]--;
        }
        for(int i = 0; i < n; i++){
            for(int j = 0; j < n; j++){
                double dist=abs(billP[billNum[i]]-billP[billNum[j]]);
                // £ª50ÈºÈç¹ðìéÆ¯ÉAßèûðüêÄ¨­
                if(dist<50||EQ(dist,50)){
                    d[billNum[i]][billNum[j]]=dist;
                    prv[billNum[i]][billNum[j]]=billNum[i];
                }
            }
        }
        warshall_floyd();
        int m;
        cin>>m;
        for(int i=0;i<m;i++){
            int s,g;
            cin>>s>>g;
            s--;g--;
            if(EQ(d[s][g],INF))
                cout<<"NA"<<endl;
            else{
                vector<int> v;
                int cp=g;
                while(1){
                    v.push_back(cp+1);
                    if(cp==s)
                        break;
                    cp=prv[s][cp];
                }
                for(int j = v.size()-1; j >= 0; j--){
                    cout<<v[j];
                    if(j==0)cout<<endl;
                    else cout<<" ";
                }
            }
        }
    }

  return 0;
}