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 <cmath>

using namespace std;

/*?§?????????????*/
struct node {
	vector<int> edges_to;
	vector<double> edges_cost;
	int n_edges, done, from, exist;
	double cost;
};

struct building {
	int x, y, exist;
};

/*??¢??°??????????????????*/
double buidingInterval(int x1, int y1, int x2, int y2);
void getPath(struct node *nodes, int start);

int main() {
	int n, m, num, s, g, path[1001];
	struct node nodes[1001];
	struct building b[1001];

	while (cin >> n, n) {
		/*?????????*/
		for (int i = 0; i < 1001; i++) {
			nodes[i].edges_to.clear();
			nodes[i].edges_cost.clear();
			nodes[i].n_edges = 0;
			nodes[i].done = 0;
			nodes[i].cost = -1;
			nodes[i].from = -1;
			nodes[i].exist = 0;
			b[i].x = -1;
			b[i].y = -1;
			b[i].exist = 0;
		}

		/*??\???*/
		for (int i = 0; i < n; i++) {
			cin >> num;
			cin >> b[num].x >> b[num].y;
			b[num].exist = 1;
			nodes[num].exist = 1;
		}


		/*?????????????????????*/
		for (int i = 1; i < 1001; i++) {
			if (b[i].exist) {
				for (int j = 1; j < 1001; j++) {
					if (b[j].exist && i != j) {
						int x1 = b[i].x,
							y1 = b[i].y,
							x2 = b[j].x,
							y2 = b[j].y;
						double bi = buidingInterval(x1, y1, x2, y2);

						if (bi <= 50) {
							nodes[i].edges_to.push_back(j);
							nodes[i].edges_cost.push_back(bi);
							nodes[i].n_edges++;
							//nodes[j].edges_to.push_back(j);
							//nodes[j].edges_cost.push_back(bi);
							//nodes[j].n_edges++;
						}
					}
				}
			}
		}

		cin >> m;
		for (int i = 0; i < m; i++) {
			cin >> s >> g;

			/*???????????????????????????????????????????????±??¨??????????????°???????????????*/
			getPath(nodes, s);

			/*?????????????´?*/
			int cont = 0, from = nodes[g].from;
			while (from != -1) {
				path[cont] = from;
				from = nodes[from].from;
				cont++;
			}

			/*????????????*/
			if (path[cont-1] == s) {
				for (int j = cont - 1; j >= 0; j--) {
					cout << path[j] << ' ';
				}
				cout << g << endl;
			}
			else {
				cout << "NA" << endl;
			}
		}
	}

	return 0;
}


/*??¢??°??????*/
double buidingInterval(int x1, int y1, int x2, int y2) {
	/*2?????????????????§?¨????????????????????????¢?????????*/
	return sqrt((double)(((x1-x2)*(x1-x2)) + ((y1-y2)*(y1-y2))));
}

void getPath(struct node *nodes, int start) {
	/*?????????????????????*/
	int to, from;
	double cost;
	struct node *done_node;

	nodes[start].cost = 0;

	while (1) {
		done_node = NULL;

		/*?¢???????????????????????¨??????????????????????????????????????????????????????????*/
		for (int i = 1; i < 1001; i++) {
			if (nodes[i].exist) {
				if (nodes[i].done || nodes[i].cost == -1) {
					continue;
				}
				else if (done_node == NULL || nodes[i].cost < done_node->cost) {
					done_node = &nodes[i];
					from = i;
				}
			}
		}
		/*?¢????????????????????????????????????????*/
		if (done_node == NULL)	break;

		/*?????????????¢?????????????*/
		done_node->done = 1;

		/*???????¢???????????????????????????\?¶????????????±?????´??°*/
		for (int i = 0; i < done_node->n_edges; i++) {
			to = done_node->edges_to[i];
			cost = done_node->cost + done_node->edges_cost[i];

			if (nodes[to].cost == -1 || (!(nodes[to].done) && cost < nodes[to].cost)) {
				nodes[to].cost = cost;
				nodes[to].from = from;
			}
		}
	}
}

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

using P = pair<double, int>;

struct edge {
    int to;
    double weight;
};

constexpr double INF = 1e10;

int main() {
    int n;
    while(cin >> n, n) {
        vector<int> x(n), y(n);
        for(int i=0; i<n; ++i) {
            int b;
            cin >> b;
            b--;
            cin >> x[b] >> y[b];
        }

        vector<vector<edge>> g(n);
        for(int i=0; i<n; ++i) {
            for(int j=0; j<n; ++j) {
                if(i != j && (x[i] - x[j]) * (x[i] - x[j]) + (y[i] - y[j]) * (y[i] - y[j]) <= 2500) {
                    g[i].push_back((edge){j, sqrt(hypot(x[i]-x[j], y[i]-y[j]))});
                }
            }
        }

        int m;
        cin >> m;
        for(int i=0; i<m; ++i) {
            int s, t;
            cin >> s >> t;
            s--; t--;
            vector<double> d(n, INF), prev(n, -1);
            d[s] = 0;
            priority_queue<P, vector<P>, greater<P>> que;
            que.push(make_pair(0, s));
            while(!que.empty()) {
                P p = que.top();
                que.pop();
                int v = p.second;
                if(d[v] < p.first) {
                    continue;
                }
                for(auto& e : g[v]) {
                    if(d[e.to] > d[v] + e.weight) {
                        d[e.to] = d[v] + e.weight;
                        prev[e.to] = v;
                        que.push(make_pair(d[e.to], e.to));
                    }
                }
            }
            if(d[t] == INF) {
                cout << "NA" << endl;
            } else {
                vector<int> path = {t+1};
                while(prev[t] != -1) {
                    path.push_back(prev[t]+1);
                    t = prev[t];
                }
                for(int i=path.size()-1; i>=0; --i) {
                    cout << path[i] << " \n"[i == 0] << flush;
                }
            }
        }
    }
}