Go: package main

import (
	"fmt"
	"os"
	"bufio"
	"strconv"
	"container/list"
)

const MaxNode int = 100

var d []int
var A [][]int
var N int
var l *list.List

func bfs(u int) {
	d[u] = 0
	l.PushBack(u)
	for ;l.Len() != 0; {
		u = l.Front().Value.(int)
		l.Remove(l.Front())
		for v:=0; v<N; v++ {
			if A[u][v] == 0 {
				continue
			}
			if d[v] != -1 {
				continue
			}
			d[v] = d[u] + 1
			l.PushBack(v)
		}
	}
}


func nextInt(scanner *bufio.Scanner) int {
	scanner.Scan()
	num, _ := strconv.Atoi(scanner.Text())
	return num
}

func print() {
	for i:=0; i<N; i++ {
		fmt.Printf("%d %d\n", i+1, d[i])
	}
}

func initVariable() {
	d = make([]int, MaxNode)
	A = make([][]int, MaxNode)
	l = list.New()
	for i:=0; i<MaxNode; i++ {
		A[i] = make([]int, MaxNode)
		d[i] = -1
	}
}


func main() {
	initVariable()
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	N = nextInt(scanner)
	for i:=0; i<N; i++ {
		idx := nextInt(scanner)
		cnt := nextInt(scanner)
		for j:=0; j<cnt; j++ {
			node := nextInt(scanner)
			A[idx-1][node-1] = 1 
		}
	}
	bfs(0)
	print()
}

C++: /*
#include<iostream>
#include<queue>
#include<algorithm>
#define INF 999999999
using namespace std;

int res[101];
int G[101][101] = {0};

int main() {
    int n, u, v, k;
    std::queue<int> Q;
    std::cin >> n;
    for (int i = 0; i < n; i++) {
        std::cin >> u >> k;
        for (int j = 0; j < k; j++) {
            std::cin >> v;
            G[u - 1][v - 1] = 1;
        }
    }

    for (int i = 0; i < n; i++) res[i] = INF;

    Q.push(0);
    res[0] = 0;

    while (! Q.empty()) {
        u = Q.front();
        for (int i = 0; i < n; i++) {
            if (G[u][i]) {
                Q.push(i);
                res[i] = std::min(res[i], res[u] + 1);
                G[u][i] = 0;
            }
        }
        Q.pop();
    }

    for (int i = 0; i < n; i++) {
        if (res[i] != INF) std::cout << i + 1 << " " << res[i] << "\n";
        else std::cout << i + 1 << " -1\n";
    }

    return 0;
}
*/

#include<iostream>
#include<queue>

using namespace std;
static const int N = 100;
static const int INFTY = (1 << 21);

int n, M[N][N];
int d[N];   // 距離で訪問状態（color）を管理する

void bfs(int s) {
    queue<int> q;   // 標準ライブラリのqueueを使用
    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] == 0) 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);

    return 0;
}

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

using namespace std;

const int WHITE = 0, GREY = 1, BLACK = 2;
const int INF = 1000000;

struct BFS {
    int n;
    vector<vector<int>> g;
    vector<int> parent;
    vector<int> distance;
    vector<int> color;
    
    BFS (int n) : n(n) {
        g.assign(n, vector<int>(0));
        parent.assign(n, -2);
        distance.assign(n, INF);
        color.assign(n, WHITE);
    }
    
    void addEdge (int u, int v) {
        g[u].push_back(v);
    }
    
    void bfs (int s) {
        queue<int> q;
        q.push(s);
        parent[s] = -1;
        distance[s] = 0;
        color[s] = GREY;
        while (!q.empty()) { //u = current, v = neighbors
            int u = q.front();
            q.pop();
            for (int v : g[u]) {
                if (color[v] == WHITE) {
                    q.push(v);
                    parent[v] = u;
                    distance[v] = distance[u] + 1;
                    color[v] = GREY;
                }
            }
            color[u] = BLACK;
        }
    }
    
    void printResults () {
        for (int i = 0; i < n; i++) {
            int dist = distance[i];
            if (dist == INF) {
                dist = -1;
            }
            cout << i + 1 << " " << dist << endl;
        }
    }
};

int main() {
    
    int n;
    cin >> n;
    BFS bfs(n);
    
    for (int i = 0; i < n; i++) {
        int u, k;
        cin >> u >> k;
        for (int j = 0; j < k; j++) {
            int v;
            cin >> v;
            bfs.addEdge(u - 1, v - 1);
        }
    }
    
    bfs.bfs(0);
    bfs.printResults();
    
    return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

using ll = long long;

ll MAX_N = 1e5;
vector<vector<ll> > graph(MAX_N);
vector<bool> visited(MAX_N);

// ALDS1_11_C
vector<ll> d(MAX_N);

// O(E)
void bfs(ll u){
    queue<pair<ll, ll> > Q; // v, dist
    visited[u] = true;
    Q.push(make_pair(u, 0));
    while(!Q.empty()){
        pair<ll, ll> p = Q.front(); Q.pop();
        ll u = p.first, dist = p.second;
        //
        d[u] = dist;
        for(ll v: graph[u]){
            if(!visited[v]){
                visited[v] = true;
                Q.push(make_pair(v, dist + 1));
            }
        }
    }
}

// ALDS1_11_C: verified
int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    ll n; cin >> n;
    for(ll i=0;i<n;i++){
        ll u, k; cin >> u >> k;
        for(ll j=0;j<k;j++){
            ll v; cin >> v;
            graph[u - 1].push_back(v - 1);
        }
    }
    fill(d.begin(), d.end(), -1);
    bfs(0);
    for(ll i=0;i<n;i++) cout << i + 1 << " " << d[i] << endl;
}

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

using namespace std;
static const int N = 100;
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] == 0) 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);

    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

static const int N = 100;
static const unsigned int INF = (1 << 31);

int n,m[N][N];
int dist[N];

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