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 <queue>
#include <algorithm>
#include <cmath>
using namespace std;

const int size = 1001;
const double inf = 1<<24;
int n;
int b[size];
int x[size], y[size];
double costs[size][size];
int con[size][size];
int con_cnt[size];

typedef pair <double, int> PDI;
typedef priority_queue <PDI, vector <PDI>, greater <PDI> > QUEUE;
double mc[size];
int prev[size];

void dijkstra_init() {
    for ( int i = 0; i < size; i++ ) {
        mc[i] = inf;
        prev[i] = -1;
    }
}

void dijkstra( int start, int goal ) {
    QUEUE Q;
    PDI start_node( 0.0, start );
    Q.push( start_node );
    mc[start] = 0.0;
    
    while ( !Q.empty() ) {
        PDI node = Q.top();
        Q.pop();

        double c = node.first;
        int v = node.second;

        if ( v == goal ) {
            vector <int> route;
            int t = v;
            route.push_back( v );
            while ( prev[t] != -1 ) {
                route.push_back( prev[t] );
                t = prev[t];
            }
            reverse( route.begin(), route.end() );
            for ( vector <int> ::iterator it = route.begin(); it != route.end(); it++ ) {
                cout << (*it) + 1;
                if ( it + 1 != route.end() ) {
                    cout << " ";
                } else {
                    cout << endl;
                }
            }
            return;
        }

        for ( int i = 0; i < con_cnt[v]; i++ ) {
            int next_v = con[v][i];
            double next_c = c + costs[v][next_v];
            if ( next_c >= mc[next_v] ) continue;
            mc[next_v] = next_c;
            prev[next_v] = v;
            PDI next_node( next_c, next_v );
            Q.push( next_node );
        }
    }

    cout << "NA" << endl;
}

int main() {
    while ( cin >> n && n ) {
        // init
        for ( int i = 0; i < n; i++ ) {
            con_cnt[i] = 0;
        }

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

        for ( int i = 0; i < n; i++ ) {
            for ( int j = 0; j < n; j++ ) {
                if ( i == j ) continue;
                costs[i][j] = hypot( x[i]-x[j], y[i]-y[j] );
                if ( costs[i][j] > 50.0 ) continue;
                con[i][con_cnt[i]++] = j;
            }
        }

        // proc
        int m;
        cin >> m;
        for ( int i = 0; i < m; i++ ) {
            int s, g;
            cin >> s >> g;
            dijkstra_init();
            dijkstra( s-1, g-1 );
        }
    }
    return 0;
}

C++: #include <functional>
#include <algorithm>
#include <iostream>
#include <numeric>
#include <iomanip>
#include <utility>
#include <cstdlib>
#include <sstream>
#include <bitset>
#include <vector>
#include <cstdio>
#include <ctime>
#include <queue>
#include <deque>
#include <cmath>
#include <stack>
#include <list>
#include <map>
#include <set>

using namespace std;

typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;

#define dump(x)  cerr << #x << " = " << (x) << endl
#define rep(i,n) for(int i=0;i<(n);i++)
#define all(a)  (a).begin(),(a).end()
#define pb push_back


int main() {
    int n;
    while(cin>>n){
        if(n==0)break;
        
        int b[2000]={},x[2000]={},y[2000]={};
        rep(i,n){
            cin>>b[i]>>x[i]>>y[i];
            b[i]--;
        }
        
        double data[200][200]={};
        rep(i,n) rep(j,n) data[i][j]=99999999;
        int prev[200][200]={};

        rep(i,n){
            rep(j,n){
                double res=sqrt( pow(x[i]-x[j],2) + pow(y[i]-y[j],2) );
                if(res<=50.0){
                    data[i][j]=res;
                    prev[i][j]=i;
                }
            }
        }
        
        rep(k,n){
            rep(i,n){
                rep(j,n){
                    if( data[i][k]+data[k][j] < data[i][j] ){
                        data[i][j] = data[i][k]+data[k][j];
                        prev[i][j]=prev[k][j];
                    }
                    data[i][j]=min( data[i][k]+data[k][j] , data[i][j] );
                }
            }
        }
        
        int m;
        cin>>m;
        
        int s,g;
        rep(i,m){
            cin>>s>>g;
            s--,g--;
            if(data[s][g]!=99999999){
                stack<int> ans;
                int pre=g;
                while(pre!=s){
                    ans.push(pre);
                    pre=prev[s][pre];
                }
                cout<<s+1;
                while(ans.size()){
                    cout<<" "<<ans.top()+1;
                    ans.pop();
                }
                cout<<endl;
            }
            else cout<<"NA"<<endl;
        }
    }
    return 0;
}