Go: package main

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

type AdjacentList struct {
	matrix [][]int
}

func NewEmptyAdjacentList(dim int) *AdjacentList {
	matrix := make([][]int, dim)
	for i := 0; i < dim; i++ {
		matrix[i] = make([]int, dim)
	}
	return &AdjacentList{matrix: matrix}
}

func (al *AdjacentList) set(node int, adjacent int) {
	al.matrix[node-1][adjacent-1] = 1
}

func (al *AdjacentList) findAdjacentsFor(node int) []int {
	adjacents := []int{}
	for i, v := range al.matrix[node-1] {
		if v == 1 {
			adjacents = append(adjacents, i+1)
		}
	}
	return adjacents
}

type DistanceList struct {
	list []int
}

func NewDistanceList(dim int) *DistanceList {
	list := make([]int, dim)
	for i := 0; i < dim; i++ {
		list[i] = -1
	}
	return &DistanceList{list: list}
}

func (dl *DistanceList) set(node int, distance int) {
	dl.list[node-1] = distance
}

func (dl *DistanceList) get(node int) int {
	return dl.list[node-1]
}

func (dl *DistanceList) isVisited(node int) bool {
	return dl.list[node-1] >= 0
}

type Position struct {
	node     int
	distance int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	dim, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	al := NewEmptyAdjacentList(dim)

	for i := 1; i <= dim; i++ {
		node, err := nextInt(sc)
		if err != nil {
			panic(err)
		}

		adjacentNum, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		for j := 0; j < adjacentNum; j++ {
			adjacent, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			al.set(node, adjacent)
		}
	}

	dl := NewDistanceList(dim)

	bfs(al, dl)

	for i := 1; i <= dim; i++ {
		fmt.Printf("%d %d\n", i, dl.get(i))
	}
}

func bfs(al *AdjacentList, dl *DistanceList) {
	stack := []Position{Position{node: 1, distance: 0}}
	for len(stack) > 0 {
		currentPosition := stack[0]
		stack = stack[1:]
		if !dl.isVisited(currentPosition.node) {
			dl.set(currentPosition.node, currentPosition.distance)
		}
		for _, v := range al.findAdjacentsFor(currentPosition.node) {
			if !dl.isVisited(v) {
				stack = append(stack, Position{node: v, distance: currentPosition.distance + 1})
			}
		}
	}
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

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

struct node {
	std::vector<int> child;
	int distance;
};

int main() {
	int node_num;

	std::cin >> node_num;

	std::vector<node> n(node_num);

	for (int i = 0; i < node_num; i++) {
		int num, to, node_val;
		std::cin >> node_val >> num;
		for (int j = 0; j < num; j++) {
			std::cin >> to;
			n[node_val - 1].child.push_back(to);
		}
		n[i].distance = -1;
	}

	//???????????????????????¢0
	n[0].distance = 0;
	std::queue<int> q;
	int dist = 1;
	q.push(1);
	while(q.size() != 0){
		int num = q.front();
		q.pop();
		for (std::vector<int>::iterator it = n[num - 1].child.begin(); it != n[num - 1].child.end(); it++) {
			if (n[*it - 1].distance > n[num - 1].distance + 1|| n[*it - 1].distance == -1) {
				n[*it - 1].distance = n[num - 1].distance + 1;
				q.push(*it);
			}
		}
	}

	for (int i = 0; i < node_num; i++) {
		std::cout << i + 1 << " " << n[i].distance << std::endl;
	}
	return 0;
}

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

int main() {
    int N;
    cin>>N;
    vector<vector<int> > graph(N);
    int u, k, tmp;
    for(int i=0;i<N;++i){
        cin>>u>>k;
        for(int j=0;j<k;++j){
            cin>>tmp;
            tmp--;
            graph[i].push_back(tmp);
        }
    }
    queue<int> que;
    queue<int> passque;
    que.push(0);
    passque.push(0);
    int node, pass;
    vector<int> ans(N);
    for(int i=0;i<N;++i){
        ans[i] = -1;
    }
    map<int, int> past;
    past[0]++;
    while(!que.empty()){
        node = que.front();que.pop();
        pass = passque.front();passque.pop();
        ans[node] = pass;
        for(int i=0;i<graph[node].size();++i){
            if(past[graph[node][i]]==0){
                que.push(graph[node][i]);
                passque.push(pass + 1);
            }
            past[graph[node][i]]++;
        }
    }
    for(int i=0;i<N;++i){
        cout<<i+1<<" "<<ans[i]<<endl;
    }
}

C++: #include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <stack>
#include <queue>
#include <cmath>
#include <string>
using namespace std;
typedef vector<int> vint;
typedef vector<long long> vll;
typedef pair<int,int> pint;
typedef long long ll;
#define range(i,a,b) for(int i=a;i<b;++i)
#define rep(i,n) range(i,0,n)
#define INF 10000000000 //10^10
#define PI 3.141592
#define pb push_back

int main(){
    //内部処理は0indexで行う

    //入力
    int n;
    cin >> n;
    vector<vint> adj(n);
    rep(i,n){
        int u,k;
        cin >> u >> k;
        rep(j,k){
            int v;
            cin >> v;
            adj[u-1].pb(v-1);
        }
    }

    //計算
    vint d(n,-1);
    d[0]=0;
    queue<int> Q;
    Q.push(0);
    while(!Q.empty()){
        int cur=Q.front(); Q.pop();
        rep(i,adj[cur].size()){
            int dst=adj[cur][i];
            if(d[dst]==-1){
                d[dst]=d[cur]+1;
                Q.push(dst);
            }
        }
    }

    //出力
    rep(i,n){
        cout << i+1 << ' ' << d[i] << endl;
    }
}

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

static const int N=100;
static const int INF=(1<<21);

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

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

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

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

using namespace std;

template<typename ISTREAM>
void readGraphList(ISTREAM& cin, vector< vector<int> >& graphList) {
	size_t n;
	cin >> n;
	graphList = vector< vector<int> >(n);
	for (size_t i = 0; i != n; ++i) {
		size_t u;
		size_t k;
		cin >> u;
		cin >> k;
		vector<int>& v = graphList.at(u - 1);
		v.resize(k);
		for (size_t j = 0; j != k; ++j) {
			cin >> v.at(j);
			v.at(j)--;
		}
	}
}
#if 1
void widthSearch(const vector<vector<int>>& graphList) {
	const size_t n = graphList.size();
	queue<int> nodeQueue;
	vector<int> distanceList(n, -1);
	nodeQueue.push(0);
	while (!nodeQueue.empty()) {
		const int id = nodeQueue.front();
		int& currentNodeDistance = distanceList.at(id);
		++currentNodeDistance;
		const vector<int>& adjList = graphList.at(id);
		for (const auto& adjID : adjList) {
			int& adjDistance = distanceList.at(adjID);
			if (adjDistance != -1)continue;
			nodeQueue.push(adjID);
			adjDistance = currentNodeDistance;
		}
		nodeQueue.pop();
	}
	for (int i = 0; i != n; ++i) {
		cout << i + 1 << " " << distanceList.at(i) << endl;
	}
}
#endif

template<typename T>
void execute(T& cin) {
	vector< vector<int> > graphList;
	readGraphList(cin, graphList);
	widthSearch(graphList);
}

int main()
{
	execute(cin);

	return 0;
}