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 <sstream>
#include <map>
#include <queue>
#include <cmath>
using namespace std;

typedef pair <double, int> PDI;
typedef pair <PDI, vector <int> > PPV;
typedef priority_queue <PPV, vector <PPV>, greater <PPV> > QUEUE;

const double eps = 1e-9;
const int size = 1001;
int n, m;
int b[size], x[size], y[size];
map <int, int> cor;
bool path[size][size];
double cost[size][size];
double min_cost[size][size];
int con[size][size];
int concnt[size];

// <=
bool big_equal( double a, double b )
{
    if ( a < b + eps ) return true;
    return fabs( a - b ) < eps;
}

double getDistance( int x1, int y1, int x2, int y2 )
{
    double x = ( x2 - x1 ), y = ( y2 - y1 );
    return sqrt( x * x + y * y );
}

// dijkstra
string solve( int s_, int g_ )
{
    int start = cor[s_], goal = cor[g_];
    if ( !path[start][goal] ) return "NA";

    vector <int> min_route;
    double minc = (double)( 1<<24 );
    QUEUE Q;
    PPV start_node( PDI( 0.0, start ), vector<int>() );
    Q.push( start_node );

    while ( !Q.empty() ) {
        PPV node = Q.top();
        Q.pop();

        double c = node.first.first;
        int ind = node.first.second;
        int number = b[ind];
        vector <int> route = node.second;
        route.push_back( number );

        // goal
        if ( number == g_ ) {
            if ( !( minc < c ) ) {
                min_route = route;
                minc = c;
            }
        }

        for ( int i = 0; i < concnt[ind]; i++ ) {
            int next_ind = con[ind][i];
            double next_c = c + cost[ind][next_ind];
            if ( !( min_cost[ind][next_ind] < next_c ) ) {
                min_cost[ind][next_ind] = next_c;
                PPV next_node( PDI( next_c, next_ind ), route );
                Q.push( next_node );
            }
        }
    }

    ostringstream os;
    for ( vector <int> ::iterator it = min_route.begin(); it != min_route.end(); it++ ) {
        os << *it;
        if ( it + 1 != min_route.end() ) os << " ";
    }

    return os.str();
}

int main( void )
{
    while ( cin >> n && n ) {
        // init
        for ( int i = 0; i < n; i++ ) {
            for ( int j = 0; j < n; j++ ) {
                path[i][j] = false;
                min_cost[i][j] = (double)(1<<24);
            }
            concnt[i] = 0;
        }

        // input
        for ( int i = 0; i < n; i++ ) {
            cin >> b[i] >> x[i] >> y[i];
            cor[b[i]] = i;
        }

        for ( int i = 0; i < n; i++ ) {
            for ( int j = 0; j < n; j++ ) {
                if ( i == j ) continue;
                cost[i][j] = getDistance( x[i], y[i], x[j], y[j] );
            }
        }

        // proc
        for ( int i = 0; i < n; i++ ) {
            for ( int j = 0; j < n; j++ ) {
                if ( i == j ) continue;
                if ( !( cost[i][j] > 50.0 ) ) {
                    path[i][j] = path[j][i] = true;
                    con[i][concnt[i]] = j;
                    concnt[i]++;
                    con[j][concnt[j]] = i;
                    concnt[j]++;
                }
            }
        }

        for ( int i = 0; i < n; i++ ) {
            for ( int j = 0; j < concnt[i]; j++ ) {
                for ( int k = 0; k < concnt[i]; k++ ) {
                    if ( j == k ) continue;
                    int a = con[i][j], b = con[i][k];
                    if ( cost[i][a] < cost[i][b] ) {
                        swap( con[i][j], con[i][k] );
                    }
                }
            }
        }

        // floyd-warshall
        for ( int k = 0; k < n; k++ ) {
            for ( int i = 0; i < n; i++ ) {
                for ( int j = 0; j < n; j++ ) {
                    if ( i == k || k == j || j == i ) continue;
                    if ( !path[i][k] || !path[k][j] ) continue;
                    path[i][j] = true;
                }
            }
        }

        // query
        cin >> m;
        for ( int i = 0; i < m; i++ ) {
            int s, t;
            cin >> s >> t;
            cout << solve( s, t ) << endl;
        }
    }
    return 0;
}

C++: #include <bits/stdc++.h>
#define INF 1e9
using namespace std;
typedef long long ll;
typedef pair<int,int> P;
int n;
ll G[101][101];

void dijkstra(int s,int g){
  ll D[101],from[101];
  from[g]=-1;
  for(int i=0;i<101;i++) D[i]=INF;
  priority_queue<P,vector<P>,greater<P> > Q;
  D[s]=0;
  Q.push(P(0,s));
  while(!Q.empty()){
    P t=Q.top(); Q.pop();
    ll pos=t.second,cost=t.first;
    if(pos==g) break;
    if(D[pos]<cost) continue;

    for(int i=0;i<n;i++){
      if(G[pos][i]==-1)continue;
      if(cost+G[pos][i]<D[i]) {
	Q.push(P(cost+G[pos][i],i));
	D[i]=cost+G[pos][i];
	from[i]=pos;
      }
    }
  }

  if(from[g]==-1){cout<<"NA"<<endl;return;}
    
  vector<int> res;
  res.push_back(g);
  int pos=g;
  while(pos!=s){
    pos=from[pos];
    res.push_back(pos);
  }

  for(int i=0;i<res.size();i++){
    if(i) cout<<" ";
    cout<<res[res.size()-1-i]+1;
  }
  cout<<endl;
}



int main(){
  while(cin>>n,n){

  double x[101],y[101];
  for(int i=0;i<n;i++){
    int b;
    cin>>b;
    cin>>x[b-1]>>y[b-1];
  }
  
  for(int i=0;i<n;i++)
    for(int j=i+1;j<n;j++){
      ll X=(x[i]-x[j]);
      ll Y=(y[i]-y[j]);
      ll dis=X*X+Y*Y;
      if(dis>50*50)G[i][j]=-1;
      else G[i][j]=G[j][i]=dis;
    }
  
  
  int m;
  cin>>m;
  while(m--){
    int s,g;
    cin>>s>>g;
    dijkstra(s-1,g-1);
  }
  }
  return 0;
}