Go: package main

import (
	"bufio"
	"os"
	"strconv"
	"strings"
	"fmt"
)

var scanner = bufio.NewScanner(os.Stdin)
const INF = 1<<31

func main() {
	scanner.Scan()
	n, _ := strconv.Atoi(scanner.Text())
	arr := make([][]int, n)
	for i := range arr {
		arr[i] = make([]int, n)
	}
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			arr[i][j] = INF
		}
	}
	for i := 0; i < n; i++ {
		scanner.Scan()
		buf := strings.Split(scanner.Text(), " ")
		input := make([]int, len(buf))
		for j := range input {
			input[j], _ = strconv.Atoi(buf[j])
		}
		x, k := input[0]-1, input[1]
		for j := 0; j < k; j++ {
			y := input[j+2]-1
			arr[x][y] = 1
		}
	}
	for k := 0; k < n; k++ {
		arr[k][k] = 0
		for i := 0; i < n; i++ {
			if arr[i][k] >= INF {
				continue
			}
			for j := 0; j < n; j++ {
				if arr[k][j] >= INF {
					continue
				}
				arr[i][j] = min(arr[i][j], arr[i][k]+arr[k][j])
			}
		}
	}
	scanner.Scan()
	p, _ := strconv.Atoi(scanner.Text())
	for i := 0; i < p; i++ {
		scanner.Scan()
		buf := strings.Split(scanner.Text(), " ")
		input := make([]int, len(buf))
		for j := range input {
			input[j], _ = strconv.Atoi(buf[j])
		}
		s, d, v := input[0]-1, input[1]-1, input[2]
		if arr[s][d] < v {
			fmt.Println(arr[s][d]+1)
		} else {
			fmt.Println("NA")
		}
	}
}

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

C++: #include<iostream>
#include<stack>
#include<vector>
#include <map>
#include <queue>
#include<string.h>
using namespace std;
typedef pair<int,int> P;

int main()
{
  int n;
  int node[100][100];
  cin>>n;
  for(int i=0;i<100;i++)
    for(int j=0;j<100;j++)
      node[i][j]=0;
  
  
  for(int x=0;x<n;x++)
    {
      int k,t;
      cin>>k>>t;
      for(int i=0;i<t;i++)
	{
	  int tmp;
	  cin>>tmp;
	  node[k][tmp]=1;
	}
    }
  int p;
  cin>>p;
  for(;p--;)
    {
      int s,d,v;
      cin>>s>>d>>v;
      queue<P> qu;
      int ans=-1;
      if(v>1)
	for(int i=0;i<=n;i++)
	  {
	    if(node[s][i]==1)
	      qu.push(P(i,2));
	  }
      bool move[n+1];
      for(int i=0;i<=n;i++)
	{
	  move[i]=true;
	}
      while(!qu.empty())
	{
	  P a = qu.front();
	  qu.pop();
	  //	  cout<<"Queue:"<<a.first<<"  "<<a.second<<endl;
	  if(a.first==d)
	    {
	      ans = a.second;
	      break;
	    }
	  if(a.second<v)    
	    for(int i=1;i<=n;i++)
	      {
		if(node[a.first][i]==1)
		  {
		    if(move[i])
		      {
			qu.push(P(i,a.second+1));
			move[i]=false;
		      }
		  }
	      }
	}
      if(ans==-1)
	cout<<"NA"<<endl;
      else
	cout<<ans<<endl;
    }
}

C++: #include<iostream>
using namespace std;
const int maxv=100000;
int main()
{
	int root[101][101];
	for(int i=0;i<10;i++){
		for(int i2=0;i2<10;i2++){
			root[i][i2]=maxv;
		}
	}
	int n;
	cin>>n;
	for(int i=0;i<n;i++){
	int r,k,ch;
	cin>>r>>k;
		for(int i2=0;i2<k;i2++){
			cin>>ch;
			root[r][ch]=1;
		}
	}

	for(int k=1;k<=n;k++){
		for(int i=1;i<=n;i++){
			for(int i2=01;i2<=n;i2++){
				root[i][i2]=min(root[i][i2],root[i][k]+root[k][i2]);
			}
		}
	}

	int m;
	int s,d,v;
	cin>>m;
	for(int i=0;i<m;i++){
		cin>>s>>d>>v;
		if(root[s][d]<v){
			cout<<root[s][d]+1<<endl;
		}
		else{
			cout<<"NA"<<endl;
		}
	}
}

C++: #include <stdio.h>
#include <cmath>
#include <algorithm>
#include <queue>

using namespace std;

struct Packet{
	Packet(){
		ttl = current = 0;
	}

	void copy(Packet t){
		ttl = t.ttl;
		current = t.current;
		for(int i=0; i < 101; i++)checkTable[i] = t.checkTable[i];
	}

	Packet(int arg_ttl,int loc){
		ttl = arg_ttl;
		for(int i=0; i < 101; i++)checkTable[i] = 0;
		checkTable[loc] = 1;
		current = loc;
	}

	void set(int loc){
		checkTable[loc] = 1;
		current = loc;
	}

	int ttl,checkTable[101],current;
};

int main(){

	int n,r,k,to,table[101][101],num_of_packet,start,goal,t_limit,memo[101][101];
	Packet tmp;

	for(int i=1; i < 101; i++){
		for(int k=1; k < 101; k++){
			table[i][k] = 0;
			memo[i][k] = 0;
		}
	}

	scanf("%d",&n);

	for(int i = 0; i < n; i++){
		scanf("%d %d",&r,&k);
		for(int p=0;p < k; p++){
			scanf("%d",&to);
			table[r][to] = 1;
		}
	}

	scanf("%d",&num_of_packet);

	queue<Packet> Q;
	bool FLG;

	for(int i=0; i < num_of_packet; i++){
		scanf("%d %d %d",&start,&goal,&t_limit);

		FLG = false;

		if(t_limit <= 1){
			printf("NA\n");
			FLG = true;
		}

		if(!FLG){
			if(memo[start][goal] != 0){
				if(memo[start][goal] <= t_limit){
					printf("%d\n",memo[start][goal]);
				}else{
					printf("NA\n");
				}
				FLG = true;
			}
		}

		if(!FLG){
			for(int i = 1; i <= n; i++){
				if(i != start && table[start][i] == 1){
					if(memo[i][goal] > 0 && memo[i][goal] < t_limit){
						printf("%d\n",memo[i][goal]+1);
						memo[start][goal] = memo[i][goal]+1;
						FLG = true;
						break;
					}
					Packet p(t_limit-1,start);
					p.set(i);
					Q.push(p);
				}
			}
		}

		while(!Q.empty()){
			tmp = Q.front();
			Q.pop();

			if(tmp.ttl > 0 && tmp.current == goal){
				printf("%d\n",t_limit - tmp.ttl+1);
				FLG = true;

				while(!Q.empty())Q.pop();

				memo[start][goal] = t_limit - tmp.ttl+1;

				break;
			}

			if(tmp.ttl > 1){
				for(int i=1; i <= n; i++){
					if(i != tmp.current && tmp.checkTable[i] == 0 && table[tmp.current][i] == 1){
						if(memo[i][goal] > 0 && memo[i][goal] < tmp.ttl){
							printf("%d\n",t_limit-tmp.ttl+1+memo[i][goal]);
							memo[start][goal] = t_limit-tmp.ttl+1+memo[i][goal];
							FLG = true;
							while(!Q.empty())Q.pop();
							break;
						}

						Packet p;
						p.copy(tmp);
						p.ttl--;
						p.set(i);
						Q.push(p);
					}
				}
			}
			if(FLG)break;
		}

		if(!FLG){
			printf("NA\n");
		}

	}

    return 0;
}

C++: #include <iostream>
#include <sstream>
#include <iomanip>
#include <algorithm>
#include <cmath>
#include <string>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <numeric>
#include <climits>
#include <cfloat>
using namespace std;

void shortestPath(const vector<vector<int> >& edges, int start, vector<int>& dist)
{
    dist.assign(edges.size(), -1);
    dist[start] = 0;
    queue<int> q;
    q.push(start);

    while(!q.empty()){
        int v = q.front();
        q.pop();
        for(unsigned i=0; i<edges[v].size(); ++i){
            int u = edges[v][i];
            if(dist[u] == -1){
                dist[u] = dist[v] + 1;
                q.push(u);
            }
        }
    }
}

void shortestPath(const vector<vector<int> >& edges, vector<vector<int> >& dist)
{
    dist.resize(edges.size());
    for(unsigned i=0; i<edges.size(); ++i)
        shortestPath(edges, i, dist[i]);
}


int main()
{
    int n;
    cin >> n;
    vector<vector<int> > edges(n+1);
    for(int i=0; i<n; ++i){
        int r, k;
        cin >> r >> k;
        edges[r].resize(k);
        for(int j=0; j<k; ++j)
            cin >> edges[r][j];
    }
    vector<vector<int> > dist;
    shortestPath(edges, dist);

    int p;
    cin >> p;
    for(int i=0; i<p; ++i){
        int s, d, v;
        cin >> s >> d >> v;
        int num = dist[s][d];
        if(num == -1 || num >= v)
            cout << "NA" << endl;
        else
            cout << (num+1) << endl;
    }

    return 0;
}