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<iostream>
#include<sstream>
#include<utility>
#include<map>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;
typedef long long ll;
typedef pair<int,double>P;
typedef struct d{int i,x,y;}d;
typedef struct q{int c,p,o,b[1005];}q;
vector<d>B;
vector<P>g[1005];
int N,M,S,G,c[1005];

struct Order{bool operator ()(q const&a, q const&b) const{return a.c>b.c;}};

void dij(int S,int G)
{
	memset(c,0x7f,sizeof(c));
	c[S]=0;
	priority_queue<q,vector<q>,Order>Q;
	q tmp={0,S,1};
	tmp.b[0]=S;
	Q.push(tmp);
	for(;!Q.empty();)
	{
		tmp=Q.top();Q.pop();
		if(tmp.p==G)
		{
			for(int i=0;i<tmp.o;i++)
				printf("%d%c",tmp.b[i],i==tmp.o-1?'\n':' ');
			return;
		}
		if(tmp.c>c[tmp.p])continue;
		for(int i=0;i<g[tmp.p].size();i++)
		{
			P np=g[tmp.p][i];
			if(c[np.first]>tmp.c+np.second)
			{
				c[np.first]=tmp.c+np.second;
				q ins={c[np.first],np.first,tmp.o+1};
				memcpy(ins.b,tmp.b,sizeof(tmp.b));
				ins.b[tmp.o]=np.first;
				Q.push(ins);
			}
		}
	}
	puts("NA");
}

int main()
{
	for(;scanf("%d",&N),N;)
	{
		B.clear();
		for(int i=0;i<N;i++)g[i].clear();
		for(int i=0;i<N;i++)
		{
			int x,y,b;
			scanf("%d%d%d",&b,&x,&y);
			d t={b,x,y};
			B.push_back(t);
		}
		for(int i=0;i<N;i++)
			for(int j=i;j<N;j++)
			{
				if(i!=j)
				{
					double l=sqrt((double)(B[i].x-B[j].x)*(B[i].x-B[j].x)+(B[i].y-B[j].y)*(B[i].y-B[j].y));
					if(l<=50.0)
					{
						g[B[i].i].push_back(make_pair(B[j].i,l));
						g[B[j].i].push_back(make_pair(B[i].i,l));
					}
				}
			}
		scanf("%d",&M);
		for(;M--;)
		{
			scanf("%d%d",&S,&G);
			dij(S,G);
		}
	}
}

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

struct Edge {
  int src, dst, w;
};

typedef vector<vector<Edge> > Graph;
typedef pair<int,int> Pair;

const int INF = 1<<28;

vector<int> dijkstra(int src, int dst, const Graph &g) {
  int n = g.size();
  priority_queue< Pair,vector<Pair>,greater<Pair> > que;
  vector<int> cost(n, INF), prev(n);
  cost[src] = 0;
  que.push(Pair(0, src));
  while(que.size()) {
    const Pair s = que.top();
    que.pop();
    if(cost[s.second] < s.first) continue;
    if(s.second == dst) {
      vector<int> path;
      int p = dst;
      while(1) {
        path.push_back(p);
        if(p == src) break;
        p = prev[p];
      }
      reverse(path.begin(), path.end());
      return path;
    }
    for(int i = 0; i < g[s.second].size(); ++i) {
      const Edge &e = g[s.second][i];
      Pair t(s.first + e.w, e.dst);
      if(cost[t.second] <= t.first) continue;
      que.push(t);
      cost[t.second] = t.first;
      prev[t.second] = s.second;
    }
  }
  return vector<int>();
}

int main() {
  int n;
  while(cin >> n && n) {
    map<int,int> id, rid;
    vector<int> x(n), y(n);
    for(int i = 0; i < n; ++i) {
      int b;
      cin >> b >> x[i] >> y[i];
      id[b] = i;
      rid[i] = b;
    }
    Graph g(n);
    for(int i = 0; i < n; ++i) {
      for(int j = i+1; j < n; ++j) {
        int cost = (x[i]-x[j])*(x[i]-x[j]) + (y[i]-y[j])*(y[i]-y[j]);
        if(cost <= 50*50) {
          cost=  1;
          g[i].push_back((Edge){i,j,cost});
          g[j].push_back((Edge){j,i,cost});
        }
      }
    }
    int m;
    cin >> m;
    while(m--) {
      int src, dst;
      cin >> src >> dst;
      vector<int> v = dijkstra(id[src], id[dst], g);
      if(v.empty()) {
        cout << "NA" << endl;
      } else {
        for(int i = 0; i < v.size(); ++i) {
          if(i) cout << " ";
          cout << rid[v[i]];
        }
        cout << endl;
      }
    }
  }
  return 0;
}

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

#define MAX 1010
#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;
	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;
}