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++: // 2011/08/25 Tazoe



#include <iostream>

#include <climits>
#include <stack>

using namespace std;



int main()

{

	while(true){

		int n;

		cin >> n;

		if(n==0)

			break;



		int B[1000][3];

		for(int i=0; i<n; i++)

			cin >> B[i][0] >> B[i][1] >> B[i][2];

/*

		for(int i=0; i<n; i++)

			cout << B[i][0] << ' ' << B[i][1] << ' ' << B[i][2] << endl;

*/

		int D[1000][1000];

		for(int i=0; i<n; i++){

			for(int j=0; j<n; j++){

				int dis = (B[i][1]-B[j][1])*(B[i][1]-B[j][1])+(B[i][2]-B[j][2])*(B[i][2]-B[j][2]);

				if(dis<=2500)

					D[i][j] = dis;

				else

					D[i][j] = INT_MAX;

			}

		}


		int P[1000][1000];

		for(int i=0; i<n; i++)

			for(int j=0; j<n; j++)

				P[i][j] = i;

/*
		for(int i=0; i<n; i++){

			for(int j=0; j<n; j++){

				if(D[i][j]==INT_MAX)

					cout << '-' << ' ';

				else

					cout << P[i][j] << ' ';

			}

			cout << endl;

		}

*/
		for(int k=0; k<n; k++){
			for(int i=0; i<n; i++){
				for(int j=0; j<n; j++){
					if(D[i][k]==INT_MAX||D[k][j]==INT_MAX)
						continue;

					if(D[i][j]>D[i][k]+D[k][j]){
						D[i][j] = D[i][k]+D[k][j];
						P[i][j] = P[k][j];
					}
				}
			}
		}
/*
		for(int i=0; i<n; i++){

			for(int j=0; j<n; j++){

				if(D[i][j]==INT_MAX)

					cout << '-' << ' ';

				else

					cout << P[i][j] << ' ';

			}

			cout << endl;

		}

*/
		int m;
		cin >> m;

		for(int i=0; i<m; i++){
			int s, g;
			cin >> s >> g;
			int S, G;
			for(int j=0; j<n; j++){
				if(B[j][0]==s)
					S = j;
				if(B[j][0]==g)
					G = j;
			}

			if(D[S][G]==INT_MAX){
				cout << "NA" << endl;
				continue;
			}

			stack<int> st;
			while(S!=G){
				st.push(G);
				G = P[S][G];
			}

			cout << B[S][0];
			while(!st.empty()){
				cout << ' ' << B[st.top()][0];
				st.pop();
			}
			cout << endl;
		}
	}



	return 0;

}

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 = i + 1; j < n; j++) {
        int xx = x[i] - x[j], yy = y[i] - y[j];
        if (pow(xx, 2) + pow(yy, 2) <= 2500 && i != j) g[i][j] = g[j][i] = sqrt(pow(xx, 2) + pow(yy, 2));
      }
    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]);
        }
      }
      for (int i = 0; i < n; i++) cerr << dist[i] << endl;
      cerr << endl;
      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;
      }
    }
  }
}

C++: #include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <cmath>
using namespace std;

#define MAX 1100
#define INF (1<<29)
#define EPS 1e-9

struct Point{
  int x, y, id;
};

vector<Point> bill;
double dist[MAX][MAX];
int prev[MAX];
int V;

void init(){
  bill.clear();
  for(int i = 0 ; i < MAX ; i++){
    for(int j = 0 ; j < MAX ; j++){
      dist[i][j] = INF;
      if(i == j) dist[i][j] = 0;
    }
  }
}

void dijkstra(int s){
  int d[MAX];
  bool used[MAX];
  fill(d, d+MAX, INF);
  fill(used, used+MAX, false);
  fill(prev, prev+MAX, -1);
  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;
    
    for(int u = 0 ; u < V ; u++){
      if(d[u] > d[v] + dist[v][u]){
	d[u] = d[v] + dist[v][u];
	prev[u] = v;
      }
    }
  }
}

vector<int> get_path(int t){
  vector<int> path;
  for(; t != -1 ; t = prev[t]) path.push_back(t);
  reverse(path.begin(), path.end());
  return path;
}

inline double getDist(int from, int to){
  double ret = sqrt( ((bill[from].x - bill[to].x)*(bill[from].x - bill[to].x)) +
		     ((bill[from].y - bill[to].y)*(bill[from].y - bill[to].y)) );
  return ret;
}
  
int main(){
  while(cin >> V, V){
    init();
    Point p;
    for(int i = 0 ; i < V ; i++){
      cin >> p.id >> p.x >> p.y;
      p.id--;
      bill.push_back(p);
    }
    
    for(int i = 0 ; i < V ; i++){
      for(int j= 0 ; j < V ; j++){
	double dis = getDist(bill[i].id, bill[j].id);
	//if(dis >= 50 + EPS) continue;
	if(dis < 50 + EPS){
	dist[bill[i].id][bill[j].id] = dist[bill[j].id][bill[i].id] = dis;
	}
      }
    }
    int m;    
    cin >> m;
    int s, g;
    while(m--){
      cin >> s >> g;
      s--, g--;
      dijkstra(s);
      vector<int> ans_path = get_path(g);
      if(ans_path.size() <= 1) cout << "NA" << endl;
      else{
	for(int i = 0 ; i < (int)ans_path.size() ; i++){
	  if(i == (int)ans_path.size()-1) cout << ans_path[i]+1 << endl;
	  else cout << ans_path[i]+1 << ' ';
	}
      }
    } 
  }
  return 0;
}