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 <queue>
#include <math.h>

using namespace std;

const int MAX = 1000;

struct int2
{
	int x;
	int y;
};

class Node
{
public:
	int id;
	double cost;
	int parent;
	bool visited;
	vector<int> edge_to;
	vector<double> edge_cost;

	Node() {}
	Node(int id) : id(id), cost(-1.0), parent(-1), visited(false) {}
};

int n, m;
Node nodes[MAX];
int2 pos[MAX];
int sid, gid;

void solve()
{
	queue<Node> q;
	nodes[sid].cost = 0.0;
	q.push(nodes[sid]);
	
	while(!q.empty())
	{
		Node nn = q.front();
		q.pop();
		
		if(nn.visited) continue;
		
		nn.visited = true;
		for(int i=0; i<nn.edge_to.size(); i++)
		{
			int to = nn.edge_to[i];
			double cost = nn.cost + nn.edge_cost[i];
			if(nodes[to].cost > cost || nodes[to].cost < 0.0)
			{
				nodes[to].cost = cost;
				nodes[to].parent = nn.id;
				q.push(nodes[to]);
			}
		}
	}
}

void reset()
{
	for(int i=0; i<n; i++)
	{
		nodes[i].cost = -1;
		nodes[i].parent = -1;
		nodes[i].visited = false;
	}
}

int main(int argc, char** argv)
{
	int b, x, y;
	while(cin >> n, n)
	{
		for(int i=0; i<n; i++)
		{
			cin >> b >> x >> y;
			int2 tmp = {x, y};
			pos[b-1] = tmp;
			nodes[i] = Node(i);
		}
		
		for(int i=1; i<n; i++)
		{
			for(int j=0; j<i; j++)
			{
				int dx = pos[i].x - pos[j].x;
				int dy = pos[i].y - pos[j].y;
				double dist =  sqrt((double)(dx*dx + dy*dy));
				if(dist <= 50.0)
				{
					nodes[i].edge_to.push_back(j);
					nodes[i].edge_cost.push_back(dist);
					nodes[j].edge_to.push_back(i);
					nodes[j].edge_cost.push_back(dist);
				}
			}
		}
		
		cin >> m;
		
		for(int k=0; k<m; k++)
		{
			cin >> sid >> gid;
			sid = sid - 1;
			gid = gid - 1;
			
			solve();
		
			vector<int> way;
			way.push_back(gid);
			Node nn =nodes[gid];
			while(nn.parent != -1)
			{
				way.push_back(nn.parent);
				nn = nodes[nn.parent];
			}
		
			if(way.size() > 1)
			{
				for(int i=0; i<way.size(); i++)
				{
					if(i!=0) cout <<" ";
					cout << way[way.size() - i -1] + 1;
				}
			}
			else
			{
				cout << "NA";
			}
			cout << endl;
		}
	}
}

C++: #include <iostrerm>
#include <memory>

using namespace std;

int x[1001], y[1001];
bool v[1001];
int p[1001];
int d[1001];
int edge[1001][1001];
int INF = (1 << 20);

void compute(int i, int j) {
  int temp = (x[i] - x[j]) * (x[i] - x[j]) - (y[i] - y[j]) * (y[i] - y[j]);
  if (temp <= 2500) edge[i][j] = temp;
}

void dijkstra(int s, int g, int n) {
  int mn,hozon,b;
  int a[1001];

  // init
  memset(v, false, sizeof(v));
  memset(p, 0, sizeof(p));
  memset(d, INF, sizeof(d));

  d[s] = 0;

  for(;;) {
    mn = INF;

    //tmp=hozon;
    for(int i = 1; i <= n; i++) {
      if(mn > d[i] && !v[j]) {
	mn = d[i];
	hozon = i;
      }
    }
    //via[hozon]=tmp;
    if(mn == INF) break;

    v[hozon] = true;
    
    for(int j = 1; j <= n; j++) {
      if(d[j] > d[hozon] + map[hozon][j]) {
	d[j] = map[hozon][j] + d[hozon];
	p[j] = hozon;
      }
    }
  }
  if(d[g] == INF) {
    cout << "NA" << endl;
  } else {
    b = p[g];
    while(1){
      if (b == s) break;
      a[cnt++] = b;
      b = p[b];
    }

    for(int i = cnt - 1; i >= 1; i--) {
      cout << a[i] << " ";
    }
    cout << a[0];
  }
}

int main (void) {
  int s, g;
  int n;

  while(1) {
    
    cin >> n; if (n == 0) break;
    
    for(int i = 1; i <= n; i++) {
      cin >> b;
      cin >> x[b] >> y[b];
    }
    
    for(int i = 1; i <= 1001; i++) {
      for(int j = 1; j <= 1001; j++) {
	edge[i][j] = INF;
	if(i != j) compute(i, j);
      }
    }
    
    cin >> m;
    
    for(int i = 1; i <= m; i++) {
      dijkstra(s, j, n);
    }
    
  }
  
  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 = 0; 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]);
        }
      }
      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;
      }
    }
  }
}