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 <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <ctime>
#include <cassert>
#include <iostream>
#include <cctype>
#include <sstream>
#include <string>
#include <list>
#include <vector>
#include <queue>
#include <set>
#include <stack>
#include <map>
#include <utility>
#include <numeric>
#include <algorithm>
#include <iterator>
#include <bitset>
#include <complex>
#include <fstream>
using namespace std;
typedef long long ll;
const double EPS = 1e-9;
typedef vector<int> vint;
typedef pair<int, int> pint;
#define rep(i, n) REP(i, 0, n)
#define ALL(v) v.begin(), v.end()
#define MSG(a) cout << #a << " " << a << endl;
#define REP(i, x, n) for(int i = x; i < n; i++)
template<class T> T RoundOff(T a){ return int(a+.5-(a<0)); }
template<class T, class C> void chmax(T& a, C b){ if(a < b) a = b; }
template<class T, class C> void chmin(T& a, C b){ if(b < a) a = b; }
template<class T, class C> pair<T, C> mp(T a, C b){ return make_pair(a, b); }

struct Bill
{
	int b, x, y;
};

#define SQR(x) ((x) * (x))
const int INF = 1 << 30;

int prv[1024];
bool dijkstra(vector<Bill>& bill, vint& ntoi, int s, int t)
{
	int V = bill.size();
	
	vint used(V, false);
	vint d(V, INF);
	d[s] = 0;
	
	while(true)
	{
		int v = -1;
		for(int u = 0; u < V; u++)
		{
			if(!used[u] && (v == -1 || d[u] < d[v]))
			{
				v = u;
			}
		}
		
		if(v == -1) break;
		
		used[v] = true;
		
		rep(u, V) if(SQR(bill[v].x - bill[u].x) + SQR(bill[v].y - bill[u].y) <= 2500)
		{
			if(d[v] + 1 < d[u])
			{
				d[u] = d[v] + SQR(bill[v].x - bill[u].x) + SQR(bill[v].y - bill[u].y);
				prv[u] = v;
			}
		}
	}
	
	return d[t] == INF;
}

int main()
{
    int n;
	
	while(cin >> n && n)
	{
		vector<Bill> bill(n);
		vint ntoi(1001, -1);
		rep(i, n)
		{
			cin >> bill[i].b >> bill[i].x >> bill[i].y;
			ntoi[bill[i].b] = i;
		}
		
		int m;
		cin >> m;
		rep(i, m)
		{
			int s, b;
			cin >> s >> b;
			
			memset(prv, -1, sizeof prv);
			
			if(dijkstra(bill, ntoi, ntoi[s], ntoi[b]))
			{
				cout << "NA" << endl;
			}
			else
			{
				vint path;
				for(int t = ntoi[b]; t != -1; t = prv[t]) path.push_back(bill[t].b);
				
				reverse(ALL(path));
				
				rep(i, path.size()) cout << path[i] << (i + 1 == path.size() ? "\n" : " ");
			}
		}
	}
}

C++: #include <iostream>
#include <sstream>
#include <map>
#include <queue>
#include <cmath>
using namespace std;

typedef pair <double, int> PDI;
typedef pair <PDI, vector <int> > PPV;
typedef priority_queue <PPV, vector <PPV>, greater <PPV> > QUEUE;

const double eps = 1e-9;
const int size = 1001;
int n, m;
int b[size], x[size], y[size];
map <int, int> cor;
bool path[size][size];
bool able[size][size];
double cost[size][size];
double min_cost[size][size];
int con[size][size];
int concnt[size];

// <
bool big_equal( double a, double b )
{
    if ( a < b ) return true;
    return fabs( a - b ) < eps;
}

double getDistance( int x1, int y1, int x2, int y2 )
{
    double x = ( x2 - x1 ), y = ( y2 - y1 );
    return sqrt( x * x + y * y ) + eps;
}

string solve( int s_, int g_ )
{
    int start = cor[s_], goal = cor[g_];
    if ( !able[start][goal] ) return "NA";

    ostringstream os;
    QUEUE Q;
    PPV start_node( PDI( 0.0, start ), vector<int>() );
    Q.push( start_node );

    while ( !Q.empty() ) {
        PPV node = Q.top();
        Q.pop();
        double c = node.first.first;
        int ind = node.first.second;
        int number = b[ind];
        vector <int> route = node.second;
        route.push_back( number );

        if ( number == g_ ) {
            for ( vector <int> ::iterator it = route.begin(); it != route.end(); it++ ) {
                os << *it;
                if ( it + 1 != route.end() ) os << " ";
            }
            break;
        }

        for ( int i = 0; i < concnt[ind]; i++ ) {
            int next_ind = con[ind][i];
            double next_c = c + cost[ind][next_ind];
            if ( min_cost[ind][next_ind] < -0.5 || big_equal( min_cost[ind][next_ind], next_c ) ) {
                min_cost[ind][next_ind] = next_c;
                PPV next_node( PDI( next_c, next_ind ), route );
                Q.push( next_node );
            }
        }

    }

    return os.str();
}

int main( void )
{
    while ( cin >> n && n ) {
        // init
        for ( int i = 0; i < n; i++ ) {
            for ( int j = 0; j < n; j++ ) {
                path[i][j] = false;
                able[i][j] = false;
                min_cost[i][j] = -1.0;
            }
            concnt[i] = 0;
        }

        // input
        for ( int i = 0; i < n; i++ ) {
            cin >> b[i] >> x[i] >> y[i];
            cor[b[i]] = i;
        }

        for ( int i = 0; i < n; i++ ) {
            for ( int j = i+1; j < n; j++ ) {
                cost[i][j] = cost[j][i] = getDistance( x[i], y[i], x[j], y[j] );
            }
        }

        // proc
        for ( int i = 0; i < n; i++ ) {
            for ( int j = i+1; j < n; j++ ) {
                if ( big_equal( cost[i][j], 50.0 ) ) {
                    path[i][j] = path[j][i] = able[i][j] = able[j][i] = true;
                    con[i][concnt[i]] = j;
                    concnt[i]++;
                    con[j][concnt[j]] = i;
                    concnt[j]++;
                }
            }
        }

        for ( int k = 0; k < n; k++ ) {
            for ( int i = 0; i < n; i++ ) {
                for ( int j = 0; j < n; j++ ) {
                    if ( i == k || k == j || j == i ) continue;
                    if ( !able[i][k] || !able[k][j] ) continue;
                    able[i][j] = true;
                }
            }
        }

        // query
        cin >> m;
        for ( int i = 0; i < m; i++ ) {
            int s, t;
            cin >> s >> t;
            cout << solve( s, t ) << endl;
        }
    }
    return 0;
}