Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)
	nodes := make([]Node, n)

	for i := 0; i < n; i++ {
		nodes[i].list = make([]int, 0)
		nodes[i].d = -1
	}

	for i := 0; i < n; i++ {
		u := getNextInt(scanner)
		k := getNextInt(scanner)
		u--
		for ii := 0; ii < k; ii++ {
			v := getNextInt(scanner)
			v--
			nodes[u].list = append(nodes[u].list, v)
		}
	}

	queue := make([]int, n)
	queue[0] = 0
	nodes[0].d = 0
	d := 0
	i, j := 0, 1
	for i < j {
		d++
		prev := j
		for i < prev {
			for k, l := 0, len(nodes[queue[i]].list); k < l && i < n; k++ {
				if nodes[nodes[queue[i]].list[k]].d != -1 {
					continue
				}
				nodes[nodes[queue[i]].list[k]].d = d
				queue[j] = nodes[queue[i]].list[k]
				j++
			}
			i++
		}
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d", i+1, nodes[i].d))
	}

	writer.Flush()
}

// Node ...
type Node struct {
	list []int
	d    int
}

C++: #include <iostream>
#include <queue>
using namespace std;
static const int N = 1000;
static const int INFTY = (1 << 21);

int n, M[N][N];
int d[N];

void bfs(int s) {
	queue<int> q;
	q.push(s);
	for (int i = 0; i < n; ++i) d[i] = INFTY;
	d[s] = 0;
	int u;
	while (!q.empty()) {
		u = q.front(); q.pop();
		for (int v = 0; v < n; ++v) {
			if (!M[u][v]) continue;
			if (d[v] != INFTY) continue;
			d[v] = d[u] + 1;
			q.push(v);
		}
	}
	for (int i = 0; i < n; ++i) {
		cout << i + 1 << " " << ((d[i] == INFTY) ? (-1) : d[i]) << endl;
	}
}

int main() {
	int u, k, v;

	cin >> n;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < n; ++j) M[i][j] = 0;
	}

	for (int i = 0; i < n; ++i) {
		cin >> u >> k;
		u--;
		for (int j = 0; j < k; ++j) {
			cin >> v;
			v--;
			M[u][v] = 1;
		}
	}
	bfs(0);
}

C++: #include<iostream>
#include<queue>
using namespace std;

int n;;
int A[101][101];
int d[101];

void bfs(int r) {
	queue<int> Q;
	Q.push(r);
	d[r] = 0;
	while (!Q.empty()) {
		int t = Q.front();
		Q.pop();
		for (int i = 1; i <= n; i++) {
			if (A[t][i] && d[i] == -1) {
				d[i] = d[t] + 1;
				Q.push(i);
			}
		}
	}
}

int main() {
	int u, v, l;
	cin >> n;

	for (int i = 1; i <= n; i++) {
		d[i] = -1;
	}

	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= n; j++) {
			A[i][j] = 0;
		}
	}

	for (int i = 1; i <= n; i++) {
		cin >> u >> l;
		for (int j = 0; j < l; j++) {
			cin >> v;
			A[u][v] = 1;
		}
	}

	bfs(1);

	for (int i = 1; i <= n; i++) {
		cout << i << ' ' << d[i] << endl;
	}
	
	return 0;
}

C++: #include <stdio.h>
#include <iostream>
#include <queue>
using namespace std;

#define NODE_NUM 100

queue<int> que;

class Node
{
private:
	int next_num;
	int next_node_list[NODE_NUM];
public:
	Node();
	void AddNextNode(int id);
	bool Search(int id);
	int dist;
};

Node::Node()
{
	next_num = 0;
}

void Node::AddNextNode(int id)
{
	next_node_list[next_num] = id;
	next_num++;
}

Node Node_list[NODE_NUM + 1];

bool Node::Search(int id)
{
	for (int k = 0; k < next_num; k++) {
		if (Node_list[next_node_list[k]].dist == -1) {
			Node_list[next_node_list[k]].dist = dist + 1;
		}
	}

	for (int i = 0; i < next_num; i++) {
		if (next_node_list[i] == id) return true;
	}
	
	for (int j = 0; j < next_num; j++) {
		que.push(next_node_list[j]);
	}
	
	return false;
}

int main(void)
{
	//input
	int n;
	cin >> n;
	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u;
		cin >> k;
		Node_list[u] = Node();
		for (int j = 0; j < k; j++) {
			int v;
			cin >> v;
			Node_list[u].AddNextNode(v);
		}
	}
	
	//dist
	for (int i = 1; i <= n; i++) {
		Node_list[i].dist = -1;
	}

	Node_list[1].dist = 0;
	for (int i = 2; i <= n; i++) {
		bool ret = Node_list[1].Search(i);
		if (ret) continue;
		if (que.empty()) continue;
		do {
			ret = Node_list[que.front()].Search(i);
			que.pop();
		} while (!ret);
		while (!que.empty()) {
			que.pop();
		}
	}

	//output
	for (int i = 1; i <= n; i++) {
		cout << i << " " << Node_list[i].dist << "\n";
	}
	
	return 0;
}

C++: // ALDS1_11_C: Breadth First Search
#include <iostream>
#include <vector>
#include <algorithm>
#define INF 1000
bool debug = false;

std::vector<std::vector<int>> adjacency_list;
std::vector<int> node_distance;

void SetnodeRelationship() {
    int total; std::cin >> total;
    int max = total+1;
    /* initialize adjacency_list */
    adjacency_list.resize(max);
    for (int i=1; i<adjacency_list.size(); i++) {
        adjacency_list.at(i).resize(max);
        for (int j=1; j<adjacency_list.at(i).size(); j++) {
            adjacency_list.at(i).at(j) = 0;
        }
    }

    /* initialize node_distance */
    node_distance.resize(max);
    for (int i=1; i<node_distance.size(); i++) {
        node_distance.at(i) = INF;
    }

    /* set node relationship */
    for (int i=1; i<adjacency_list.size(); i++) {
        int node, outdegree; std::cin >> node >> outdegree;
        for (int j=0; j<outdegree; j++) {
            int tmp; std::cin >> tmp;
            adjacency_list.at(node).at(tmp) = 1;
        } 
    }
}

void BreadthFirstSearch(int node, int distance) {
    node_distance.at(node) = distance;

    /* Recerve */
    for (int i=1; i<adjacency_list.at(node).size(); i++) {
        /* have next vertex? */
        if (adjacency_list.at(node).at(i) == 1) {
            /* is the path to the next vertex SHORTEST distance? */
            if (node_distance.at(i) > distance+1) {
                if (debug) std::cout << "BreadthFirstSearch(" << i << ", " << distance+1 << ")\n";
                BreadthFirstSearch(i, distance+1);
            }
        }
    }
}

int main() {
    SetnodeRelationship();
    BreadthFirstSearch(1, 0);

    for (int i=1; i<node_distance.size(); i++) {
        if (node_distance.at(i) == INF) {
            node_distance.at(i) = -1;
        }
        std::cout << i << " " << node_distance.at(i) << "\n";
    }
}

C++: #include <stdio.h>
#include <iostream>
#include <queue>
#define NUM 100
#define NIL -1
using namespace std;

int V[NUM + 1][NUM + 1];
int dist[NUM + 1];
int node_num;
int t;
int pos;
queue<int> Q;

void init(){
    int V[NUM + 1][NUM + 1];
    for(int i = 1; i <= NUM; i++){
        for(int j = 1; j <= NUM; j++){
            V[i][j] = 0;
        }
    }

    for(int i = 0; i <= NUM; i++) {
        dist[i] = NIL;
    }
    
    t = 0;
}

void get_adj(){
    scanf("%d", &node_num);

    for(int i = 0; i < node_num; i++){
        int num1;
        scanf("%d", &num1);

        int n;
        scanf("%d", &n);

        int num2;
        for(int j = 0; j < n; j++){
            scanf("%d", &num2);
            V[num1][num2] = 1;
        }
    }
}

void touchNextNode(int n){
    t += 1;
    for(int i = 1; i <= node_num; i++){
        if(V[n][i] == 1 && dist[i] == NIL){
            Q.push(i);
            dist[i] = dist[n] + 1;
        }
    }
    Q.pop();
}

void BFS(){
    Q.push(1);
    dist[1] = t;
    touchNextNode(1);
    
    while(Q.size()){
        int pos = Q.front();
        touchNextNode(pos);
    }
}

int main(void){
    init();
    get_adj();
    BFS();
    
    for(int i = 1; i <= node_num; i++){
        printf("%d %d\n", i, dist[i]);
    }

}