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 <vector>
#include <algorithm>
#include <queue>
#include <cstring>
#include <cmath>
#include <cstdio>

#define INF 1 << 28
#define EPS 1e-5

using namespace std;

typedef double Weight; 

struct Edge{
    int src;
    int dst;
    Weight weight;

    Edge(int src, int dst, Weight weight):
        src(src), dst(dst), weight(weight){ }
};

struct Node{
    int index;
    Weight cost;
    int prev;

    Node(int index, Weight cost, int prev) :
        index(index), cost(cost), prev(prev){ }
};

bool operator <(const Node &a, const Node &b){
    if(a.cost == b.cost){
        return a.index > b.index;
    }else{
        return a.cost > b.cost;
    }
}

void dijkstra(int s, vector<Weight> &costs, vector<int> &prev, vector<vector<Edge> > &edges){
    int n=costs.size();
    priority_queue<Node> q;

    costs.assign(n,INF);
    prev.assign(n,-1);
    costs[s] = 0;
    q.push(Node(s,0,-2));

    while(!q.empty()){
        Node fix = q.top(); 
        q.pop();
        if(prev[fix.index] != -1) continue;
       
        costs[fix.index] = fix.cost;
        prev[fix.index] = fix.prev;

        for(int i=0;i<edges[fix.index].size();i++){ //foreach edge from fixed
            if(costs[edges[fix.index][i].dst] > costs[fix.index] + edges[fix.index][i].weight){
                q.push(Node(edges[fix.index][i].dst, edges[fix.index][i].weight + costs[fix.index], fix.index));
            }
        }
    }
}

vector<int> createpath(vector<int> &prev, int e){
    vector<int> ret;
    int pos = e;
    while(1){
        ret.push_back(pos);
        pos = prev[pos];
        if(pos == -2){
            reverse(ret.begin(),ret.end());
            return ret;
        }
    }
}

struct building{
    int index;
    int x;
    int y;
    
    building(int index, int x, int y):
        index(index), x(x), y(y){}
};

int main(){
    int n;
    while(cin >> n && n){
        vector<vector<Edge> > edges(n);
        vector<Weight> cost(n);
        vector<int> prev(n);
        vector<int> name(n);
        vector<building> b;
        vector<int> ans;
        double dist;
        int m;
        int src,dst;
        int index,x,y;

        for(int i=0;i<n;i++){
            cin >> name[i] >> x >> y;
            b.push_back(building(i,x,y));
        }

        for(int i=0;i<n;i++){
            for(int j=i+1;j<n;j++){
                dist = sqrt(pow(b[i].x - b[j].x,2) + pow(b[i].y - b[j].y, 2));
                if(dist <= 50.0){
                    edges[i].push_back(Edge(i,j,dist));
                    edges[j].push_back(Edge(j,i,dist));
                }
            }
        }
        
        cin >> m;
        for(int i=0;i<m;i++){
            int srcname,dstname;
            cin >> srcname >> dstname;
            for(int i=0;i<n;i++){
                if(name[i] == srcname){
                    src = i;
                }
                if(name[i] == dstname){
                    dst = i;
                }
            }
            dijkstra(src, cost, prev, edges);
            if(cost[dst] == INF){
                cout << "NA" << endl;
            }else{
                ans = createpath(prev,dst);
                for(int j=0;j<ans.size()-1;j++){
                    cout << name[ans[j]] << " ";
                }
                cout << name[ans.back()] << endl;
            }
        }
    }
}

C++: #include <iostream>
#include <complex>
#include <vector>
#include <utility>
#define rep(i,k,n) for(int i=k;i<n;i++)
#define INF 100000
using namespace std;
typedef complex<double> point; 
void makeroad(vector< vector < pair<int,double> > > &road,point* mapl,int n){
  double tmp;
  rep(i,0,n)
    rep(j,i+1,n)
      if((tmp=abs(mapl[i]-mapl[j]))<=50){
	road[i].push_back(make_pair(j,tmp));

	road[j].push_back(make_pair(i,tmp));
      }
}
int* dijk(const int n, vector< vector< pair<int,double> >  >&list,int s,int g){
  int* keiro;
  int i,j,u;
  double minn;
  double *length;
  bool *check=new bool[n];
  length= new double[n];
  keiro=new int[n];
 
  for(i=0;i<n;i++){
    length[i]=INF;    check[i]=true; keiro[i]=n+1;}
  //rep(i,0,n)
    //cout<<keiro[i]<<'!'<<endl;
  length[s]=0.0;
  while(check[g]){
    minn=(double)INF;


  
    rep(j,0,n)
      if(check[j] && (minn>length[j]) ){
	u=j; minn=length[j];}
    //cout<<u<<"!?"<<endl;
    if(minn==INF) break;
    rep(i,0,list[u].size())
      if(list[u][i].second+length[u]<length[list[u][i].first]){
	length[list[u][i].first]=list[u][i].second+length[u];
	keiro[list[u][i].first]=u;
      }  
    check[u]=false;
  }
  
  return keiro;
}



int main(){
  int n,m,ts,tg,tt;
  int* ans;
  vector<int> anss;
  double ta,tb;
  cin>>n;
  while(n){
    point mapl[n]; 
    rep(i,0,n){
      cin>>tt>>ta>>tb;
      mapl[tt-1]=point(ta,tb);
    }
    //いったんビルの情報を取りましょう
    vector<vector<pair<int,double> > > road(n);//これが道になる
    makeroad(road,mapl,n);//makeroadはmaplでroadを作
    cin>>m;
    rep(i,0,m){
      cin>>ts>>tg;
      ans=dijk(n,road,ts-1,tg-1);   
      if (ans[tg-1]>n) cout <<"NA\n";
      else{
	tt=tg-1;
	anss.resize(n);
	int k=0;
	anss[k++]=tg-1;
	for(;ans[tt]!=ts-1;tt=ans[tt]){
	  anss[k++]=ans[tt];
	}
	anss[k++]=ts-1;
	rep(l,1,k+1)
	  cout<<anss[k-l]+1<<" ";
	cout<<endl;
      }
    }
    cin>>n;
  }
  return 0;
}