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 <stdio.h>

/* ?????°???????????? */
typedef	void			VD;
typedef	signed char		I1;
typedef unsigned char 	U1;
typedef	signed short	I2;
typedef unsigned short 	U2;
typedef	signed int		I4;
typedef unsigned int 	U4;

/* ?????°?????? */
#define MAX_ROUTER 100
#define MAX_TTL 10000

#define CONNECT 1
#define DISCONNECT 0
#define SENTINEL -1

#define TRUE 1
#define FALSE 0

#define INPUT_SUCCESS 0
#define INPUT_ERORR -1

/* ????????????????????£?¨? */
VD setInit(VD);
I1 inputConnectInfo(VD);
I1 inputTransmitPacket(VD);
I4 CalcSumRouter(I4 i4Sender,I4 i4Destination,I4 i4TTL);
/* ??°?????????????????° */
I1 u1Connect[MAX_ROUTER+1][MAX_ROUTER+1];
I4 i4RouterNum;

/* main??? */
I4 main(VD)
{
	I1 i1ErrorCheck;
	I4 i4CalcNum;
	I4 i4RoopCnt1;
	I4 i4RoopCnt2;
	
	setInit();
	i1ErrorCheck = inputConnectInfo();
	if(i1ErrorCheck == INPUT_SUCCESS){
		scanf("%d",&i4CalcNum);
		for( i4RoopCnt1=0; i4RoopCnt1<i4CalcNum; i4RoopCnt1++)
		{
			inputTransmitPacket();
		}
	}
	else{
		;
	}
	return 0;
}

/* ???????????¢??° */
VD setInit(VD)
{
	I4 i4RoopCnt1;
	I4 i4RoopCnt2;
	
	for( i4RoopCnt1=1; i4RoopCnt1<=MAX_ROUTER; i4RoopCnt1++)
	{
		for(i4RoopCnt2=1; i4RoopCnt2<=MAX_ROUTER; i4RoopCnt2++)
		{
			u1Connect[i4RoopCnt1][i4RoopCnt2] = DISCONNECT;
		}
	}
	return;
}

/* ??????????????\?¶??????±??\?????¢??° */
I1 inputConnectInfo(VD)
{
	I1 i1Return;
	I4 i4RoopCnt1;
	I4 i4RoopCnt2;
	I4 i4RouterCnt;
	I4 i4ConnectNum;
	I4 i4AccessPoint;
	
	i1Return = INPUT_SUCCESS;
	
	scanf("%d",&i4RouterNum);
	if(i4RouterNum <= (I4)MAX_ROUTER){
		for( i4RoopCnt1=1; i4RoopCnt1<=i4RouterNum; i4RoopCnt1++){
			scanf("%d%d",&i4RouterCnt,&i4ConnectNum);
			for( i4RoopCnt2=0; i4RoopCnt2<i4ConnectNum; i4RoopCnt2++){
				scanf("%d",&i4AccessPoint);
				u1Connect[i4RouterCnt][i4AccessPoint] = CONNECT;
			}
			u1Connect[i4RouterCnt][i4RouterNum+1] = SENTINEL;
		}
	}
	else{
		i1Return = INPUT_ERORR;
	}
	return i1Return;
}

/* ???????????±???????????±??\?????¢??° */
I1 inputTransmitPacket(VD)
{
	I1 i1Return;
	I4 i4StartRouter;
	I4 i4GoalRouter;
	I4 i4TTL;
	I4 i4Ans;
	
	i1Return = INPUT_SUCCESS;
	
	scanf("%d%d%d",&i4StartRouter,&i4GoalRouter,&i4TTL);
	if(i4TTL <= MAX_TTL){
		i4Ans = CalcSumRouter(i4StartRouter,i4GoalRouter,i4TTL);
		if(i4Ans > 0){
			printf("%d\n",i4Ans);
		}
		else{
			printf("NA\n");
		}
	}
	else{
		i1Return = INPUT_ERORR;
	}
	return i1Return;
}

/* ??????????????????????¨????????????°?¨??????¢??° */
I4 CalcSumRouter(I4 i4Sender,I4 i4Destination,I4 i4TTL)
{
	/* ?????°??£?¨? */
	I1 i1StarTable[MAX_ROUTER+1][MAX_ROUTER+1];	/* ????????¨ */
	I4 i4DefineRouter[MAX_ROUTER+1];
	I4 i4RoopCnt1;
	I4 i4RoopCnt2;
	I4 i4RoopCnt3;
	I4 i4StarCnt;
	I4 i4RoopMax;
	
	/* ????????? */
	i4StarCnt = 0;
	
	for( i4RoopCnt1=1; i4RoopCnt1<=i4RouterNum; i4RoopCnt1++){
		i4DefineRouter[i4RoopCnt1] = FALSE;
		for(i4RoopCnt2=1; i4RoopCnt2<=i4RouterNum; i4RoopCnt2++){
			i1StarTable[i4RoopCnt1][i4RoopCnt2] = FALSE;
		}
	}
	
	if(i4TTL<=i4RouterNum){	
		i4RoopMax = i4TTL;
	}
	else{
		i4RoopMax = i4RouterNum;
	}
	
	i4DefineRouter[i4Sender] = TRUE;
	i1StarTable[1][i4Sender] = TRUE;
	
	for(i4RoopCnt1=1; i4RoopCnt1<i4RoopMax; i4RoopCnt1++){
		for(i4RoopCnt2=1; i4RoopCnt2<=i4RouterNum; i4RoopCnt2++){
			if(i1StarTable[i4RoopCnt1][i4RoopCnt2] == TRUE){
				for(i4RoopCnt3=1; i4RoopCnt3<=i4RouterNum; i4RoopCnt3++){
					if(u1Connect[i4RoopCnt2][i4RoopCnt3] == CONNECT){
						if(i4RoopCnt3 == i4Destination){
							return i4RoopCnt1+1;
						}
						else{
							;
						}
						if(i4DefineRouter[i4RoopCnt3] != TRUE){
							i4StarCnt++;
							i4DefineRouter[i4RoopCnt3] = TRUE;
							i1StarTable[i4RoopCnt1+1][i4RoopCnt3] = TRUE;
						}
						else{
							;
						}
					}
					else{
						;
					}
				}
			}
			else{
				;
			}
		}
		if(i4StarCnt > 0){
			i4StarCnt = 0;
		}
		else{
			return 0;
		}	
	}
	return 0;
}

C++: #include<bits/stdc++.h>
#define rep(i,n)for(int i=0;i<n;i++)
using namespace std;

int cost[100][100];
int main() {
	int n; scanf("%d", &n);
	memset(cost, 0x3f, sizeof(cost));
	rep(i, n) {
		int r, k; scanf("%d%d", &r, &k);
		r--;
		rep(j, k) {
			int t; scanf("%d", &t);
			cost[r][--t] = 1;
		}
	}
	for (int k = 0; k < n; k++)
		for (int i = 0; i < n; i++)
			for (int j = 0; j < n; j++)
				cost[i][j] = min(cost[i][j], cost[i][k] + cost[k][j]);
	int p; scanf("%d", &p);
	rep(i, p) {
		int s, d, v; scanf("%d%d%d", &s, &d, &v);
		s--; d--;
		if (cost[s][d] >= v)puts("NA");
		else printf("%d\n", cost[s][d] + 1);
	}
}

C++: #include<iostream>
#include<queue>

using namespace std;

int main(){

  int n;
    cin >> n;
    
    int data[n+1][n+1];
    
    for(int i = 0; i <= n; i++){
      for(int j = 0; j <= n; j++){
	data[i][j] = 0;
      }
    }
    
    int from, to, conesum;

    for(int i = 0; i < n; i++){
      cin >> from >> conesum;
      for(int j = 0; j < conesum; j++){
	cin >> to;
	data[from][to] = 1;
      }
    }


    int sumpake;
    cin >> sumpake;

    queue<int> Q;

    int ttl, myposi, min, sumin, sumina, finish = 0;

    for(int i = 0; i < sumpake; i++){
      min = 0;
      cin >> from >> to >> ttl;
      myposi = from;
      for(int j = 0; j < ttl; j++){
	if(j != 0){
	  for(int l = 0; l < sumina; l++){
	    if(Q.front() == to){
	      min = j;
	      finish = 1;
	      break;
	    }
	    myposi = Q.front();
	    Q.pop();
	    for(int k = 1; k <= n; k++){
	      if(data[myposi][k] == 1) {
		Q.push(k);
		sumin++;
	      }
	    }
	    
	  }
	  if(finish == 1) break;
	}else{
	  sumin = 0;
	  for(int k = 1; k <= n; k++){
	    if(data[myposi][k] == 1) {
	      Q.push(k);
	      sumin++;
	    }
	  }
	  
	}
	  sumina = sumin;
	  sumin = 0;
      }
      
      if(min == 0) cout << "NA";
      else cout << min+1;
      cout << endl;
      finish = 0;
      while(!Q.empty()) Q.pop();
    }

  return 0;
}