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 <sstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <climits>
#include <cfloat>
using namespace std;

class Edge
{
public:
    int to;
    double cost;
    Edge(){};
    Edge(int to0, double cost0){to = to0; cost = cost0;}
};

void shortestPath(const vector<vector<Edge> >& edges, int start, vector<int>& prev)
{
    prev.assign(edges.size(), -1);
    vector<double> dist(edges.size(), DBL_MAX);
    dist[start] = 0.0;
    priority_queue<pair<double,int> ,vector<pair<double,int> >, greater<pair<double,int> > > q;
    q.push(make_pair(0.0, start));

    while(!q.empty()){
        pair<double, int> p = q.top();
        q.pop();
        int v = p.second;
        if(dist[v] < p.first)
            continue;
        for(unsigned i=0; i<edges[v].size(); ++i){
            Edge e = edges[v][i];
            if(dist[v] + e.cost < dist[e.to]){
                prev[e.to] = v;
                dist[e.to] = dist[v] + e.cost;
                q.push(make_pair(dist[e.to], e.to));
            }
        }
    }
}

int main()
{
    for(;;){
        int n;
        cin >> n;
        if(n == 0)
            return 0;

        vector<int> index(n), x(n), y(n);
        for(int i=0; i<n; ++i)
            cin >> index[i] >> x[i] >> y[i];

        vector<vector<Edge> > edges(n);
        for(int i=0; i<n; ++i){
            for(int j=0; j<n; ++j){
                double dist = sqrt(pow(x[i]-x[j], 2.0) + pow(y[i]-y[j], 2.0));
                if(dist <= 50){
                    edges[i].push_back(Edge(j, dist));
                }
            }
        }
        vector<vector<int> > prev(n);
        for(int i=0; i<n; ++i)
            shortestPath(edges, i, prev[i]);

        int m;
        cin >> m;
        for(int i=0; i<m; ++ i){
            int s, g;
            cin >> s >> g;
            s = find(index.begin(), index.end(), s) - index.begin();
            g = find(index.begin(), index.end(), g) - index.begin();

            if(prev[g][s] == -1)
                cout << "NA" << endl;
            else{
                int v = s;
                cout << index[v];
                while(v != g){
                    v = prev[g][v];
                    cout << ' ' << index[v];
                }
                cout << endl;
            }
        }
    }
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
	int n;
	while(cin >> n , n){
		double g[n][n];
		for(int i = 0; i < n; i++)
			for(int j = 0; j < n; j++)
				g[i][j] = 100000000;
		int b[n] , x[n] , y[n];
		for(int i = 0; i < n; i++)
			cin >> b[i] >> x[i] >> y[i];
		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(sqrt(xx * xx + yy * yy) <= 50 && i != j)
					g[i][j] = g[j][i] = sqrt(xx * xx + yy * yy);
			}
		int m;
		cin >> m;
		int s , go;
		for(int i = 0; i < m; i++){
			cin >> s >> go;
			s--; go--;
			vector <int> used(n,false);
			vector <int> gone(n,false);
			vector <double> dist(n,100000000);
			dist[s] = 0;
			gone[s] = 0;
			while(1){
				int va = -1;
				for(int j = 0; j < n; j++)
					if(used[j] == false && (va == -1 || dist[va] > dist[j]))
						va = j;
				if(va == -1)
					break;
				used[va] = true;
				for(int j = 0; j < n; j++){
					if(dist[j] >= dist[va] + g[va][j])
						gone[j] = va;
					dist[j] = min(dist[j] , dist[va] + g[va][j]);
				}
			}
			if(s == go)
				cout << s + 1 << " " << go + 1 << endl;
			else if(dist[go] == 100000000)
				cout << "NA" << endl;
			else{
				int kari = go;
				stack <int> out;
				while(1){
					out.push(gone[kari] + 1);
					kari = gone[kari];
					if(kari == s)
						break;
				}
				while(!out.empty()){
					cout << out.top() << " ";
					out.pop();
				}
				cout << go + 1 << endl;
			}
		}
	}
}