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 <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 = 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;
      }
    }
  }
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <cstring>
#include <complex>

using namespace std;

const int MAX_V = 1001;
// d[u][v]Íu©çvÖÌRXgBßÉ×Ú·éGbWÌRXgðüêÄ¨¢½è·êÎæ¢Í¸B
int d[MAX_V][MAX_V];
const int INF=1000000000;
// ¸_
int V;

#define EPS (1e-10)
#define EQ(a,b) (abs((a)-(b))<EPS)

// prv[i][j] -> iªX^[gn_ÌÆ«Aj©çÇ±Éßé©
int prv[MAX_V][MAX_V];

// S_ÎÅZoHâèðÆ­O(V^3)AÓª ÁÄà®ì
void warshall_floyd(){
    for(int i = 0; i < V; i++){
        for(int j = 0; j < V; j++){
            for(int k = 0; k < V; k++){
                //d[j][k]=min(d[j][k],d[j][i]+d[i][k]);
                if(d[j][k]>d[j][i]+d[i][k]){
                    int cp=k;
                    // XV
                    while(1){
                        prv[j][cp]=prv[i][cp];
                        cp=prv[i][cp];
                        if(cp==i)break;
                    }
                    d[j][k]=d[j][i]+d[i][k];
                }
            }
        }
    }
}

typedef complex<double> P;
int main(){
    int n;
    while(cin>>n&&n!=0){
        V=n;
        for(int i = 0; i < MAX_V; i++){
            for(int j = 0; j < MAX_V; j++){
                if(i==j)d[i][j]=0;
                else d[i][j]=INF;
                prv[i][j]=INF;
            }
        }
        int billNum[MAX_V];
        P billP[MAX_V];
        for(int i=0;i<n;i++){
            int x,y;
            cin>>billNum[i]>>x>>y;
            billP[i]=P(x,y);
            billNum[i]--;
        }
        for(int i = 0; i < n; i++){
            for(int j = 0; j < n; j++){
                double dist=abs(billP[i]-billP[j]);
                // £ª50ÈºÈç¹ðìéÆ¯ÉAßèûðüêÄ¨­
                if(dist<50||EQ(dist,50)){
                    d[i][j]=dist;
                    prv[i][j]=i;
                }
            }
        }
        warshall_floyd();
        int m;
        cin>>m;
        for(int i=0;i<m;i++){
            int s,g;
            cin>>s>>g;
            s--;g--;
            if(d[s][g]==INF)
                cout<<"NA"<<endl;
            else{
                vector<int> v;
                int cp=g;
                while(1){
                    v.push_back(cp+1);
                    if(cp==s)
                        break;
                    cp=prv[s][cp];
                }
                for(int i = v.size()-1; i >= 0; i--){
                    cout<<v[i];
                    if(i==0)cout<<endl;
                    else cout<<" ";
                }
            }
        }
    }

  return 0;
}

C++: #include<cstdio>
#include<vector>
#include<queue>
#include<utility>
#include<climits>
#include<functional>
#include<algorithm>
using namespace std;

const int N = 1001;
const int MAX_DISTANCE = 50*50;
double dis2[N][N];
template<class T>
inline T Square(T x){return (x*x);}


vector<int> F(int n, int from, int to)
{
	int i;
	pair<double, vector<int> > bill[N];
	for(i = 0; i <= n; ++i) bill[i].first = INT_MAX;

	typedef pair<double,int> PDI;
	priority_queue<PDI, vector<PDI>, greater<PDI> > q;	PDI p;

	q.push(make_pair(0, from));
	bill[from].first = 0;
	bill[from].second.push_back(from);
	while(!q.empty())
	{
		p = q.top(), q.pop();

		for(i = 1; i <= n; ++i)
		{
			if(dis2[p.second][i] <= MAX_DISTANCE &&
				bill[i].first > bill[p.second].first + dis2[p.second][i])
			{
				bill[i].first = bill[p.second].first + dis2[p.second][i];
				bill[i].second = bill[p.second].second;
				bill[i].second.push_back(i);
				q.push(make_pair(bill[i].first, i));
			}
		}
	}
	return bill[to].second;
}

int main()
{
	int n,m,i,j,b,x,y,from,to;
	pair<int,int> pos[N];	//<x, y>

	while(scanf("%d",&n),n)
	{
		for(i = 1; i <= n; ++i)
		{
			scanf("%d%d%d",&b,&x,&y);
			pos[b].first = x, pos[b].second = y;
		}
		for(i = 1; i <= n; ++i)
		{
			for(j = 1; j <= n; ++j)
			{
				if(i==j) dis2[i][j] = dis2[j][i] = MAX_DISTANCE*5;
				else
				{
					dis2[i][j] = Square(pos[i].first-pos[j].first) + Square(pos[i].second-pos[j].second);
					dis2[j][i] = dis2[i][j];
				}
			}
		}
		scanf("%d",&m);
		for(i=0;i<m;++i)
		{
			scanf("%d%d",&from,&to);
			vector<int>v = F(n,from,to);
			if( v.empty())
				puts("NA");
			else
			{
				for(vector<int>::iterator ite = v.begin(); ite != v.end(); ++ite)
				{
					printf("%s%d", (ite!=v.begin()?" ":""), *ite);
				}
				putchar('\n');
			}
		}
	}
	return 0;
}