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 <string>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <algorithm>	// require sort next_permutation count __gcd reverse etc.
#include <cstdlib>	// require abs
#include <cstdio>	// require printf
#include <functional>
#include <numeric>	// require accumulate
#include <cmath>
#include <climits>
#include <limits>
#include <cfloat>
#include <iomanip>	// require setw
#include <sstream>	// require stringstream 
#include <cstring>	// require memset
#include <cctype>	// require tolower, toupper
#include <fstream>	// require freopen
#define rep(i,n) for(int i=0;i<(n);i++)
#define ALL(A) A.begin(), A.end()
#define DEBUG 0

using namespace std;

typedef long long ll;
typedef pair<int, int> P;
typedef pair<double, int> pdi;

const int INF = 1000000000;

double adj[1005][1005];
int path[1005];
double d[1005];
int n;
bool visit[1005];

// ノード:s からの最短距離を求める
bool dijkstra (int s, int t )
{
	memset (path, -1, sizeof (d ) );
	memset (visit, false, sizeof (visit ) );
	// greater<P> を指定することでfirstが小さい順に取り出せるようにする
	priority_queue<pdi> que;

	fill (d,  d + n, INF );
	d[s] = 0.0;
	que.push (P (0.0, s ) );
	while (!que.empty() ){
		pdi p = que.top(); que.pop();
		double dis=-p.first;
		int u = p.second;
		if (u == t ) return true;
		visit[u] = true;
		rep (v, n ){
			if (visit[v] ) continue;
			if (d[v] > dis + adj[u][v] ){
				d[v] = dis + adj[u][v];
				que.push (pdi (-d[v], v ) );
				path[v] = u;
			} // end if
		} // end rep
	} // end while

	return false; 
}

void disp_path (int s, int t )
{
	vector<int> res;
	res.push_back (t );
	int curr = t;
	while (path[curr] != -1 ){
		curr = path[curr];
		res.push_back (curr );
	} // end while

	reverse (ALL (res ) );
	rep (i, res.size() ){
		cout << res[i] + 1 << (i != res.size() - 1 ? ' ' : '\n' );
	} // end rep
}

int main()
{
//	cut here before submit 
//	freopen ("testcase.spiderjin", "r", stdin );

	while (scanf ("%d", &n ) && n != 0 ){
//		memset (adj, -1, sizeof (adj ) );
		rep (i, n ) rep (j, n ) adj[i][j] = INF;
		vector<P> p;
		p.clear();
		rep (i, n ){
			int id, x, y;
			scanf ("%d %d %d", &id, &x, &y );
			p.push_back (P (x, y ) );
		} // end rep

		rep (i, n ){
			rep (j, n ){
				if (i == j ) continue;
				int xx = p[i].first - p[j].first;
				int yy = p[i].second - p[j].second;
				int dis = xx*xx + yy*yy;
				if (dis <= 50*50 ){
					adj[i][j] = sqrt (dis );
					adj[j][i] = sqrt (dis );
				} // end if
			} // end rep
		} // end rep

		int m;
		scanf ("%d", &m );
		rep (i, m ){
			int s, t;
			scanf ("%d %d", &s, &t );
			s--, t--;
			if (dijkstra (s, t ) ){
				disp_path (s, t );
			}else{
				printf ("NA\n" );
			} // end if
		} // end rep
	} // end while
	
	return 0;
}

C++: #include <iostream>
#include <cstring>
#include <vector>
#include <utility>
#include <queue>
#include <cmath>
using namespace std;
typedef pair< double, int > P;
const int inf = 1LL << 20;
int x[200],y[200];
int pre[200];
double d[200];
main()
{
    int n;
    while( cin >> n, n )
    {
        /// key is b;distance of b
        for( int i = 0; i < n; i++ ) 
        {
            int b,X,Y;
            cin >> b >> X >> Y;
            b--;
            x[b] = X;y[b] = Y;
        }
        vector< P > E[200];
        for( int i = 0; i< n; i++ ) 
        {
            for( int j = i + 1; j < n; j++ )
            {
                double f = sqrt( ( double )( x[i] - x[j] ) * ( x[i] - x[j] ) + ( y[i] - y[j] ) * ( y[i] - y[j] ) );
                if( f <= 50. )
                {
                    E[i].emplace_back( P(f, j) );E[j].emplace_back( P(f, i) ) ;
                }
            }
        }
        int m;
        cin >> m;
        for( int k = 0; k < m; k++ )
        {
            int s, g;
            cin >> s >> g;
            s--,g--;
            for( int l = 0; l < 200; l++ ) d[l] = inf;
            memset( pre, -1, sizeof( pre ) );
            priority_queue< P, vector< P >, greater<P> > q;
            d[s] = 0;
            q.push( P(0, s) );
            while( !q.empty() )
            {
                P p = q.top();
                q.pop();
                if( d[p.second] != p.first )continue;
                if( p.second == g )break;
                for( P u : E[p.second] )
                {
                    if( d[u.second] > p.first + u.first )
                    {
                        d[u.second] = p.first + u.first;
                        pre[u.second] = p.second;
                        q.push( P( d[u.second], u.second ) );

                    }
                }
            }
            if( d[g] == inf )puts("NA");
            else
            {
                vector< int > v;
                for( int u = g; ~u; v.emplace_back( u ), u = pre[u] );
                for( int i = v.size() - 1; i >= 0; i-- )
                {
                    printf( "%d", v[i] + 1);
                    if( i ) printf( " ");
                    else printf("\n");
                }
            }
        }
        
    }
    return 0;
}