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++: /* Dijkstra's Algorithm */

#include<cmath>
#include<queue>
#include<vector>
#include<iostream>

#define	mp	make_pair
#define	pb	push_back

using namespace std;

typedef	vector<int>			vi;
typedef	pair<double,int>	pdi;

const int inf=1000000000;
int n,id[1000],x[1000],y[1000];
double adj[1000][1000];

bool Dijkstra(int s,int g,int *path)
{
	double d[1000];
	bool visited[1000];
	for(int i=0;i<n;i++)	d[i]=inf,visited[i]=false;
	d[s]=0;
	priority_queue<pdi> pq;	pq.push(mp(0,s));
	while(!pq.empty()){
		pdi a=pq.top();	pq.pop();
		double dis=-a.first;
		int u=a.second;
		if(visited[u])	continue;
		if(u==g)	return true;
		visited[u]=true;
		for(int v=0;v<n;v++){
			if(visited[v])	continue;
			if(dis+adj[u][v]<d[v]){
				d[v]=dis+adj[u][v];
				pq.push(mp(-d[v],v));
				path[v]=u;
			}
		}
	}
	return false;
}

void showPath(int s,int now,int *path,int *id)
{
	if(now==s){ cout<<id[s]; return; }
	showPath(s,path[now],path,id);
	cout<<' '<<id[now];
}

int main()
{
	for(;cin>>n,n;){
		for(int i=0;i<n;i++)	cin>>id[i]>>x[i]>>y[i];

		for(int i=0;i<n;i++)for(int j=0;j<n;j++)	adj[i][j]=(i==j?0:inf);
		for(int i=0;i<n;i++)for(int j=0;j<n;j++){
			int xx=x[i]-x[j],yy=y[i]-y[j];
			if(xx*xx+yy*yy<=50*50)	adj[i][j]=sqrt(xx*xx+yy*yy);
		}

		int m;	cin>>m;
		while(m--){
			int sid,gid;	cin>>sid>>gid;
			int s,g;
			for(int i=0;i<n;i++){
				if(id[i]==sid)	s=i;
				if(id[i]==gid)	g=i;
			}

			int path[1000];
			if(Dijkstra(s,g,path)){
				showPath(s,g,path,id);
				cout<<endl;
			}
			else	cout<<"NA"<<endl;
		}
	}

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

//#define double long double

const double INF = 1e+9;

struct Point {
	int x, y;
	
	Point(int a = 0, int b = 0){
		x = a;
		y = b;
	}
};

struct Edge {
	int to;
	double cost;
	
	Edge(int a, double b){
		to = a;
		cost = b;
	}
};

struct State {
	int pos;
	double sum;
	vector<int> route;
	
	State(int a, double b, vector<int> c){
		pos = a;
		sum = b;
		route = c;
	}
	
	bool operator < (const State &t) const {
		return sum > t.sum;
	}
};

int norm(Point &a, Point &b)
{
	return (a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y);
}	

int n;
Point b[2000];
double d[2000];
vector<int> v[2000];
vector<Edge> g[2000];

void search(int s)
{
	for (int i = 0; i < 2000; i++){
		v[i].clear();
		d[i] = INF;
	}
	
	priority_queue<State> que;
	que.push(State(s, 0.0, vector<int>(0)));
	for ( ; que.size(); que.pop()){
		State st = que.top();
		if (d[st.pos] < st.sum) continue;
		
		d[st.pos] = st.sum;
		v[st.pos] = st.route;
		v[st.pos].push_back(st.pos);
		
		//cout << st.sum << endl;
		
		for (int i = 0; i < g[st.pos].size(); i++){
			Edge &e = g[st.pos][i];
			if (d[e.to] < st.sum + e.cost) continue;
			que.push(State(e.to, st.sum + e.cost, v[st.pos]));
		}
	}
}

int main()
{
	while (scanf("%d", &n), n){
		for (int i = 0; i < 2000; i++){
			g[i].clear();
		}
		
		for (int i = 0; i < n; i++){
			int B, x, y;
			scanf("%d %d %d", &B, &x, &y);
			b[--B] = Point(x, y);
		}
		
		for (int i = 0; i < n; i++){
			for (int j = 0; j < n; j++){
				if (i == j) continue;
				
				if (norm(b[i], b[j]) <= 50 * 50){
					g[i].push_back(Edge(j, sqrt(norm(b[i], b[j]))));
				}
			}
		}
		
		int m;
		scanf("%d", &m);
		for (int i = 0; i < m; i++){
			int s, g;
			scanf("%d %d", &s, &g);
			search(--s);
			
			if (v[--g].size() == 0){
				puts("NA");
				break;
			}
			
			for (int j = 0; j < v[g].size(); j++){
				if (j) printf(" ");
				printf("%d", v[g][j] + 1);
			}
			puts("");
		}
	}
	
	return 0;
}

C++: #include <iostream>
#include <string>
#include <algorithm>
#include <functional>
#include <vector>
#include <utility>
#include <cstring>
#include <iomanip>
#include <numeric>
#include <cmath>
#include <cassert>
#include <queue>
using namespace std;
using ll = long long;
using P = pair<double, int>;
const int INF = 1<<30;
const int MOD = 1e9 + 7;
const int MAX_N = 110;
int n, m;
struct edge
{
    int to; double cost;
    edge(int to, double cost) { this->to = to, this->cost = cost; }
};
vector<edge> G[MAX_N];
void print(vector<int> &pathway, int s, int g)
{
    vector<int> res;
    int v = g;
    while(true)
    {
        res.push_back(v);
        if(v == s) break;
        v = pathway[v];
    }
    reverse(res.begin(), res.end());
    for(int i = 0; i < res.size(); i++)
    {
        if(i) cout << " ";
        cout << res[i] + 1;
    }
    cout << endl;
}
void solve(int s, int g)
{
    vector<double> cost(n, INF);
    vector<int> pathway(n, -1);
    priority_queue<P, vector<P>, greater<P>> que;
    que.push(P(0, s));
    cost[s] = pathway[s] = 0;
    while(que.size())
    {
        P p = que.top(); que.pop();
        int v = p.second;
        if(v == g)
        {
            print(pathway, s, g);
            return;
        }
        for(int u = 0; u < G[v].size(); u++)
        {
            edge e = G[v][u];
            if(p.first + e.cost < cost[e.to])
            {
                cost[e.to] = p.first + e.cost;
                pathway[e.to] = v;
                que.push(P(cost[e.to], e.to));
            }
        }
    }
    cout << "NA" << endl;
}
int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    while(cin >> n, n)
    {
        for(int i = 0; i < MAX_N; i++) G[i].clear();
        vector<int> id(n), x(n), y(n);
        for(int i = 0; i < n; i++)
        {
            cin >> id[i] >> x[i] >> y[i];
            id[i]--;
        }
        for(int i = 0; i < n; i++)
        {
            for(int j = 0; j < n; j++)
            {
                if(i == j) continue;
                int a = x[i] - x[j], b = y[i] - y[j];
                double d = sqrt(a * a + b * b);
                if(d <= 50) G[id[i]].push_back(edge(id[j], d));
            }
        }
        cin >> m;
        for(int i = 0; i < m; i++)
        {
            int s, g; cin >> s >> g;
            s--, g--;
            solve(s, g);
        }
    }
    return 0;
}