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 <vector>
#include <queue>
#include <map>
using namespace std;

map<int, vector<int>> A;
int color[101];
int D[101];
int d = 0;

void dfs(int u) {
    queue<int> Q;
    Q.push(u);
    color[u] = 1;
    int current;
    D[u] = d;
    while(!Q.empty()) {
        current = Q.front();
        Q.pop();
        vector<int>::iterator it = A[current].begin();
        while(it != A[current].end()) {
            if (color[*it] == 0) {
                Q.push(*it);
                color[*it] = 1;
                D[*it] = D[current] + 1;
            }
            it++;
        }
    }
}

int main() {
    int n;
    cin >> n;

    int u, k;
    for (int i = 1; i <= n; i++) {
        color[i] = 0;
        D[i] = -1;
        cin >> u >> k;
        int ad;
        for (int j = 0; j < k; j++) {
            cin >> ad;
            A[u].push_back(ad);
        }
    }

    dfs(1);

    for (int i = 1; i <= n; i++) {
        cout << i << " " << D[i] << endl;
    }
}

C++: #include <iostream>
#include <vector>
#include <stack>
#include <queue>
#include <utility>

using vvi = std::vector<std::vector<int>>;

std::vector<int> DistanseFrom(const vvi& edges, int from)
{
    using namespace std;
    constexpr int nil = -1;

    int nextDist {};
    const int n = edges.size();
    queue<int> currentQ;
    queue<int> nextQ;
    vector<int> distances(n, nil);

    nextQ.push(from);
    distances[from] = nextDist;
    ++nextDist;

    while (!nextQ.empty())
    {
        currentQ = nextQ;
        nextQ = queue<int>();
        
        while (!currentQ.empty())
        {
            int c = currentQ.back();
            currentQ.pop();

            for (const auto& e : edges[c])
            {
                if (distances[e] == nil)
                {
                    nextQ.push(e);
                    distances[e] = nextDist;
                }
            }
        }
        
        ++nextDist;
    }

    return distances;
}

void solve()
{
    using namespace std;

    int n;
    cin >> n;

    //隣接リスト形式(1オリジン)
    vvi edges(n + 1);

    //読み込み
    for (int i = 1; i <= n; ++i)
    {
        int u, k;
        cin >> u >> k;

        edges[u] = vector<int>(k);

        for (int j = 0; j < k; ++j)
        {
            cin >> edges[u][j];
        }
    }

    auto dist = DistanseFrom(edges, 1);

    for (int i = 1; i <= n; ++i)
    {
        cout << i << " " << dist[i] << endl;
    }
}

int main()
{
    solve();
    return 0;
}

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

int main()
{
    int n;
    cin >> n;
    int adj[n][n];
    int V[n];
    for (int i = 0; i < n; i++)
    {
        int u, k;
        cin >> u >> k;
        V[i] = k;
        for (int j = 0; j < k; j++)
        {
            int v;
            cin >> v;
            adj[u - 1][j] = v - 1;
        }
    }
    queue<int> q;
    int d[n];
    for (int i = 0; i < n; i++)
        d[i] = -1;
    d[0] = 0;
    q.push(0);
    while (!q.empty())
    {
        int u = q.front();
        q.pop();
        for (int i = 0; i < V[u]; i++)
        {
            int v = adj[u][i];
            if (d[v] == -1)
            {
                d[v] = d[u] + 1;
                q.push(v);
            }
        }
    }

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

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

class Vertex {
public:
    int num;
    bool flag;                  // 以前訪れたかどうか
    vector<int> adj;            // 隣接リスト
};

int dist[101];
void bfs(map<int, Vertex>& graph, Vertex s) {
    queue<Vertex> que;

    dist[s.num] = 0;
    graph[s.num].flag = true;
    que.push(s);
    while (!que.empty()) {
        Vertex u = que.front(); que.pop();
        for (auto i = 0; i < u.adj.size(); i++) {
            Vertex v = graph[u.adj[i]];
            if (!v.flag) {
                graph[u.adj[i]].flag = true;
                dist[v.num] = dist[u.num]+1;
                que.push(v);
            }
        }
    }
}

int main(void) {
    int n;
    cin >> n;
    for (int i = 0; i < 101; i++) {
        dist[i] = -1;
    }

    map<int, Vertex> graph; // 頂点の番号->頂点
    for (int i = 0; i < n; i++) {
        Vertex v;
        int num, k;
        cin >> num >> k;
        v.flag = false;
        v.num = num;
        for (int j = 0; j < k; j++) {
            int tmp;
            cin >> tmp;
            v.adj.push_back(tmp);
        }
        graph[num] = v;
    }

    bfs(graph, graph[1]);
    for (int i = 1; i <= n; i++) {
        cout << i << " " << dist[i] << endl;
    }

    return 0;
}

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

char s[13][1];
int D[106][106];
int A[106],f[106],w,h,n,sx,sy,gx,gy,e,g[106];
int   kensa(int ,int);
int main(){
	queue<int> P;
	int i,j,a,b,c,d;
	for(i=1;i<=100;i++){
		for(j=1;j<=100;j++){
			D[i][j]=-1;		
		}					
	}						
	for(i=0;i<105;i++){		
		A[i]=0;				
		f[i]=-1;
		g[i]=0;
	}							
	scanf("%d" ,&a);//     a=4
	for(i=1;i<=a;i++){
        scanf("%d",&b);		//
		scanf("%d",&b);			//b=2					//
		for(j=1;j<=b;j++){		//
		scanf("%d",&c);			//					//
		D[i][c]=1;
//
		}						//D[???][???]
	}				
	for(i=1;i<=a;i++){
		for(j=1;j<=a;j++){
	//		printf("%d %d %d\n",i,j,D[i][j]);
		}	
	}//
	P.push(1);
	//P???1
	f[1]=0;
	while(!P.empty()){			//
		d=P.front();
		//
		A[d]=1;
		//
		P.pop();				//
		for(i=1;i<=a;i++){
			//printf("%d %d %d\n",d,i,D[d][i]);//
			if(D[d][i]==-1){		//
			continue;			//
			}					//
			if(A[i]==1){		//
			continue;			//
			}					//
			P.push(i);			//
			
			g[i]=g[d]+1;
			A[i]=1;
			//printf("%d\n",P.back());
		}	
	}							//
	for(i=1;i<=a;i++){			//
	printf("%d %d\n",i, g[i]);	//
	}
	return 0;
}