Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

func stringifyArray(arr []int) string {
	return strings.TrimRight(fmt.Sprintf("%+v", arr)[1:], "]")
}

var infty = 1000000000

type nodeKey int

type DirectedGraphNode struct {
	key       nodeKey
	adjacents []*DirectedGraphNode
	visited   bool
	d         int
	parent    *DirectedGraphNode
}

type DirectedGraph struct {
	nodes []DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(l, r nodeKey) {
	g.nodes[l].adjacents = append(g.nodes[l].adjacents, &g.nodes[r])
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]DirectedGraphNode, nNodes)
	for iNodes := 0; iNodes < nNodes; iNodes++ {
		graph.nodes[iNodes].key = nodeKey(iNodes)

		graph.nodes[iNodes].visited = false
		graph.nodes[iNodes].d = infty
		graph.nodes[iNodes].parent = nil
	}
	return &graph
}

type QueueEntry struct {
	node *DirectedGraphNode
	next *QueueEntry
}

type Queue struct {
	head, tail *QueueEntry
}

func (q *Queue) enqueue(node *DirectedGraphNode) {
	entry := QueueEntry{}
	entry.node = node

	if q.tail == nil {
		q.head = &entry
		q.tail = &entry
		return
	}

	q.tail.next = &entry
	q.tail = q.tail.next
}

func (q *Queue) dequeue() *QueueEntry {
	if q.head == nil {
		return nil
	}
	poped := q.head
	q.head = q.head.next
	if q.head == nil {
		q.tail = nil
	}
	return poped
}

func (q *Queue) isEmpty() bool {
	return q.head == nil
}

func fillDistancesByBreadthFirstSearch(g *DirectedGraph, startNode *DirectedGraphNode) {
	startNode.visited = true
	startNode.d = 0

	queue := Queue{}
	queue.enqueue(startNode)
	for !queue.isEmpty() {
		u := queue.dequeue().node
		for _, adjacent := range u.adjacents {
			if !adjacent.visited {
				adjacent.visited = true
				adjacent.d = u.d + 1
				adjacent.parent = u
				queue.enqueue(adjacent)
			}
		}
		u.visited = true
	}
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	g := newDirectedGraph(nNodes + 1)

	for iNode := 0; iNode < nNodes; iNode++ {
		nodeKeyLeft := nodeKey(nextInt())
		nAdj := nextInt()
		for iAdj := 0; iAdj < nAdj; iAdj++ {
			nodeKeyRight := nodeKey(nextInt())
			g.setAdjacency(nodeKeyLeft, nodeKeyRight)
		}
	}

	// fmt.Println(g)
	fillDistancesByBreadthFirstSearch(g, &g.nodes[1])
	// fmt.Println(g)

	for iNode := 1; iNode <= nNodes; iNode++ {
		node := g.nodes[iNode]
		distance := node.d
		if distance == infty {
			distance = -1
		}
		fmt.Println(node.key, distance)
	}
}

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;
}