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 <cmath>
using namespace std;

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

void compute(int i, int j) {
  double temp = sqrt(((double)x[i] - x[j]) * (x[i] - x[j]) + (y[i] - y[j]) * (y[i] - y[j]));
  if (temp <= 50) edge[i][j] = temp;
}

void dijkstra(int s, int g, int n) {
  int mn,hozon,b, cnt = 0;
  int a[1001];

  // init
  
  for(int i = 0; i <= 1000; i++) {
    v[i] = false;
    p[i] = 0;
    d[i] = INF;
    a[i] = 0;
  }
  
  //cout << "init: " << v[1] << " " << p[5] << " " << d[7] << " " << a[8] << endl;

  //cout << "dijkstra in" << endl;
  d[s] = 0;

  for(;;) {
    mn = INF;

    //tmp=hozon;
    for(int i = 1; i <= 1000; i++) {
      if(mn > d[i] && !v[i]) {
	mn = d[i];
	hozon = i;
      }
    }
    //via[hozon]=tmp;
    if(mn == INF) break;

    v[hozon] = true;
    
    for(int j = 1; j <= 1000; j++) {
      if(edge[hozon][j]==INF)continue;
      if(d[j] > d[hozon] + edge[hozon][j] && !v[j]) {
	//if(hozon==19)cout<<j<<" "<<d[j]<<" "<<edge[hozon][j]<<endl;
	d[j] = edge[hozon][j] + d[hozon];
	p[j] = hozon;
	//cout<<p[j]<<" "<<j<<endl;                    1657 2225 3872
      }
    }
  }
  if(d[g] == INF) {
    cout << "NA" << endl;
  } else {
    b = p[g];// cout << "goal's p: " << p[g] << endl;   842 1800 900 3542
    while(1){
      // cout << "test" << endl;
      if (b == s){
	a[cnt++]=b;
	break;
      }
      a[cnt++] = b;
      b = p[b];
    }
    
    for(int i = cnt-1; i >= 0; i--) {
      cout << a[i] << " ";
    }
    cout <<g<< endl;
  }
}

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

  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 <= 1000; i++) {
      for(int j = 1; j <= 1000; j++) {
	edge[i][j] = INF;
	if(i != j) compute(i, j);
      }
    }
    
    cin >> m; //cout << "m: " << m << endl;
    
    for(int i = 1; i <= m; i++) {
      cin >> s >> g;
      dijkstra(s, g, n);
    }
    
  }
  
  return 0;
}

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

const int EPS = 1e-6;

struct Building{
	double x,y;
}

struct Edge{
	int to;
	double dist;
	Edge(){}
	Edge(int to_c, double dist_c){
		to = to_c; dist = dist_c;
	}
};

struct Data{
	int n, cost;
	Data(){}
	Data(int n_c, int cost_c){
		n = n_c; cost = cost_c;
	}
	bool operator
}

double GetDistnace(Building b1, Building b2){
	int dx = b1.x - b2.x, dy = b1.y - b2.y;
	return sqrt(dx*dx + dy*dy);
}

vector<Edge> e[1000];

int main(){
	Building b[1000] = {};
	int N, M;
	cin >> N;
	for(int i = 0; i < N; i++){
		int indx;
		cin >> indx; indx--;
		cin >> b[indx].x >> b[indx].y;
	}
	for(int i = 0; i < N; i++){
		if(b[i].x == 0) continue;
		for(int j = 0; j < N; j++){
			if(i == j || b[j].x == 0) continue;
			double dist = GetDistance(b[i], b[j]);
			if(dist <= 50) e[i].push( Edge(j, dist) );
		}
	}
	
	cin >> M;
	for(int i = 0; i < M; i++){
		int s,g;
		cin >> s >> g; s--; g--;
		
		priority_queue<Data> pq;
		Data fpq;
		pq.push( Data(s, 0) );
		double memo[1000];
		fill_n(memo, 1000, 100000);
		while( !pq.empty() ){
			fpq = pq.top();
			if(fpq.n == g) break;
			if(memo[fpq.n] <= 10000) continue;
			for(int j = 0; j < e[fpq.n].size(); j++){
				pq.push( Data( e[fpq.n][j].to, fpq.cost + e[fpq.n][j].dist ) );
			}
		}
		vector<int> ans;
		for(int j = g; j != s;){
			for(int k = 0; k < 1000; k++){
				if( abs( memo[k] + e[j][k].dist - memo[j] ) < EPS ){
					j = k; break;
				}
			}
		}
	}
	
	return 0;
}

C++: #include <cstdio>
#include <iostream>
#include <algorithm>
#include <map>
#include <string>
#include <vector>
#include <cmath>
using namespace std;

#define REP(i,n) for(int i = 0; i < (int)(n); ++i)
#define pb push_back
#define ALL(a) (a).begin(),(a).end()

//typedef long long ll;

//const int INF = 100000000;
const int INF = 1<<28;
const int MAX_V = 1010;
const int MAX_E = 1000000;

int x[MAX_V], y[MAX_V];
double cost[MAX_V][MAX_V];
double d[MAX_V];
bool used[MAX_V];
int pre[MAX_V];
int V, E;

bool flag_end = false;

void init_cost() {
    REP(i, V) REP(j, V) cost[i][j] = INF;
}

void input() {
    scanf("%d", &V);

    if (V == 0) {
        flag_end = true;
        return;
    }

    init_cost();

    REP(i, V) {
        scanf("%*d%d%d", &x[i], &y[i]);
    }

    REP(i, V) {
        REP(j, V) {
            cost[i][j] = hypot(1.0*x[i] - x[j], 1.0*y[i] - y[j]);
        }
    }
}

//s: start
void dijkstra(int s) {
    REP(i, V) d[i] = INF;
    REP(i, V) used[i] = false;
    REP(i, V) pre[i] = -1;
    d[s] = 0.0;

    while (true) {
        int v = -1;
        REP(u, V) if (!used[u] && (v == -1 | d[u] < d[v])) v = u;

        if (v == -1) break;
        used[v] = true;

        REP(u, V) {
            if (cost[v][u] <= 50 && d[u] > d[v] + cost[v][u]) {
                d[u] = d[v] + cost[v][u];
                pre[u] = v;
            }
        }
    }
}

//t: terminal
vector<int> get_path(int t) {
    vector<int> path;
    for (; t != -1; t = pre[t]) path.pb(t);
    reverse(ALL(path));
    return path;
}

void solve() {
    int m;
    scanf("%d", &m);

    REP(i, m) {
        int s, g;
        scanf("%d%d", &s, &g);
        s--; g--;
        dijkstra(s);
        if (d[g] != INF) {
            vector<int> path = get_path(g);
            REP(i, path.size()) printf("%d ", path[i] + 1);
        } else {
            printf("NA");
        }
        printf("\n");
    }
}

int main() {
    while (true) {
        input();
        if (flag_end) return 0;
        solve();
    }
    return 0;
}