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 <algorithm>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <cstring>
#include <climits>
#include <cmath>

#define FOR(i,b,n) for(int i=b;i<n;i++)
#define CLR(mat) memset(mat, 0, sizeof(mat))

using namespace std;

int n, x[1001], y[1001], m, s[1001], g[1001], pre[1001];
double amt[1001][1001], vtx[1001];

queue<int> que;
stack<int> out;

int main()
{
	while( cin >> n, n)
	{
		CLR(amt);

		FOR(i, 0, n)
		{
			int b;
			cin >> b >> x[i] >> y[i];
		}

		cin >> m;

		FOR(i, 0, m)
		{
			cin >> s[i] >> g[i];
			s[i]--;g[i]--;
		}

		FOR(j, 0, n)
			FOR(i, j, n)
			{
				if( i != j )
				{
					double dis =  sqrt( pow((double)(x[i] - x[j]), 2) + pow((double)(y[i] - y[j]), 2) );

					if(dis <= 50.0)
					{
						amt[j][i] = dis;
						amt[i][j] = dis;
					}
				}
			}
		
		FOR(k, 0, m)
		{
			que.push(s[k]);

			FOR(i, 0, n)
			{
				vtx[i] = DBL_MAX;
			}
		
			vtx[s[k]] = 0;

			while(!que.empty())
			{
				int now = que.front();
				que.pop();

				FOR(tg, 0, n)
				{
					if( amt[now][tg] > 0 && now != tg && vtx[now] + amt[now][tg] < vtx[tg] )
					{
						vtx[tg] = vtx[now] + amt[now][tg];
						pre[tg] = now;
						que.push(tg);
					}
				}

			}

			if( vtx[g[k]] == DBL_MAX )
			{
				cout << "NA" <<endl;
			}
			else
			{
				int now = g[k];
				
				while( now != s[k] )
				{
					out.push(pre[now]);
					now = pre[now];
				}

				while( !out.empty() )
				{
					cout << out.top()+1 << " ";
					out.pop();
				}

				cout << g[k]+1 << 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++) {
      int b, _x, _y;
      cin >> b >> _x >> _y;
      x[b - 1] = _x;
      x[b - 1] = _y;
      // 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]);
        }
      }
      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;
      }
    }
  }
}