Go: package main

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

const (
	N     = 100
	INFTY = 1 << 21
)

type Graph struct {
	M [N][N]int
	d [N]int
}

func (g *Graph) bfs(s, n int) string {
	var q []int
	q = append(q, s) // push

	for i := 0; i < n; i++ {
		g.d[i] = INFTY
	}
	g.d[s] = 0

	for len(q) != 0 {
		u := q[0]
		q = q[1:] // pop
		for v := 0; v < n; v++ {
			if g.M[u][v] == 0 || g.d[v] != INFTY {
				continue
			}
			g.d[v] = g.d[u] + 1
			q = append(q, v) // push
		}
	}

	var out bytes.Buffer
	for i := 0; i < n; i++ {
		if g.d[i] == INFTY {
			out.WriteString(fmt.Sprintf("%d -1\n", i+1))
			continue
		}
		out.WriteString(fmt.Sprintf("%d %d\n", i+1, g.d[i]))
	}

	return strings.TrimRight(out.String(), "\n")
}

func answer(reader io.Reader) string {
	sc := bufio.NewScanner(reader)
	sc.Split(bufio.ScanWords)

	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())

	var g Graph
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		u--
		for j := 0; j < k; j++ {
			sc.Scan()
			v, _ := strconv.Atoi(sc.Text())
			v--
			g.M[u][v] = 1
		}
	}

	return g.bfs(0, n)
}

func main() {
	fmt.Println(answer(os.Stdin))
}

C++: #include<bits/stdc++.h>
using namespace std;
int N;
vector<int> dist;
vector<vector<int>> G;
int main(){
    cin >> N;
    dist.assign(N,-1);
    G.resize(N);
    for(int i=0;i<N;i++){
        int id;cin >> id;
        int k;cin >> k;
        for(int j=0;j<k;j++){
            int a;cin >> a;a--;
            G[i].push_back(a);
        }
    }
    queue<int> que;
    que.push(0);
    int d = 0;
    dist[0] = 0;
    while(!que.empty()){
        int now = que.front();
        que.pop();
        for(auto nv:G[now]){
            if(dist[nv]!=-1) continue;
            dist[nv] = dist[now]+1;
            que.push(nv);
        }
    }
    for(int i=0;i<N;i++){
        cout << i+1 << " " << dist[i] << endl;
    }
}

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

using std::queue;

int main() {
        int n, u, k, v;
        const int N = 100;
        bool graph[N][N] = {{false}};
        int cost[N];
        queue<int> q;
        for (int i = 0; i < N; i++) {
                cost[i] = -1;
        }

        scanf("%d", &n);
        for (int i = 0; i < n; i++) {
                scanf("%d %d", &u, &k);
                for (int j = 0; j < k; j++) {
                        scanf("%d", &v);
                        graph[u-1][v-1] = true;
                }
        }
        q.push(0);
        cost[0]++;
        while (!q.empty()) {
                int cur = q.front();
                q.pop();
                for (int to = 0; to < n; to++) {
                        if (!graph[cur][to] || cost[to] > -1) {
                                continue;
                        }
                        q.push(to);
                        cost[to] = cost[cur] + 1;
                }
        }
        for (int i = 0; i < n; i++) {
                printf("%d %d\n", i+1, cost[i]);
        }

        return 0;
}

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

const int MAX_N = 100;
int to[MAX_N][MAX_N];
int ans[MAX_N];
bool visited[MAX_N];

int main() {
  int N;
  cin >> N;
  for (int i=0; i<N; i++) {
    for (int j=0; j<N; j++) {
      to[i][j] = -1;
    }
    ans[i] = -1;
    visited[i] = false;
  }
  for (int i=0; i<N; i++) {
    int tmp, n;
    cin >> tmp >> n;
    for (int j=0; j<n; j++) {
      int t;
      cin >> t; t--;
      to[i][j] = t;
    }
  }

  queue<pair<int, int> > que;
  que.push(make_pair(0, 0));
  while (!que.empty()) {
    pair<int, int> tmp = que.front(); que.pop();
    int x = tmp.first, depth = tmp.second;
    if (ans[x] == -1) {
      ans[x] = depth;
    } else {
      continue;
    }
    for (int i=0; to[x][i] != -1; i++) {
      que.push(make_pair(to[x][i], depth + 1));
    }
  }

  for (int i=0; i<N; i++) {
    cout << i+1 << " " << ans[i] << endl;
  }
  return 0;
}

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

int n = 0;//pointing at number of line
int u = 0;//number of top
int k[101];//output order(connect)
int v[101][101];//number of top
int Short[101] = { 0 };//Short(d[v])
//into n = 0;//element count
int p = 0;//Pointer
int fptr = 0;
int lptr = 0;
int x1[10000];
int y1[10000];
void Enqueue(int y, int x)
{
	x1[lptr] = x;//top of number
	y1[lptr] = y;//shortest
	lptr = (lptr + 1) % 10000;
}
void bfs(int l) {
	int i;
	while (fptr!=lptr) {
		l=x1[fptr];
		p=y1[fptr];
		fptr = (fptr + 1) % 10000;
		if(Short[l]!=-1){
			continue;
		}
		for(i=0;i<k[l];i++){
			if(v[l][i]){
				Enqueue(p+1,v[l][i]);
			}
		}
		//Enqueue(v[l][in]);
		Short[l]=++p;
	}
}
int main()
{
	int i;
	int j;
	cin >> n;
	for (i = 0; i < n; i++) {
		cin >> u;
		cin >> k[u];
		for (j = 0; j < k[u]; j++) {
			cin >> v[u][j];
		}
	}
	Enqueue(-1,1);
	for(i=0;i<n+1;i++){
		Short[i]=-1;
	}
	bfs(0);
	
	for (i = 1; i < n + 1; i++) {
		cout << i << " " << Short[i] << endl;
	}
}

C++: #include <iostream>
#include <queue>
#include <vector>
using namespace std;
int d[128][128],solve[128];
int main(){
      //input
      int n,m,row,t;
      queue<int> que;
      cin >> n;
      for(int i= 0;i<n;i++){
            cin >>row>>m;
            for(int j = 0;j<m;j++){
                  cin>>t;
                  d[row][t] = 1;
            }
      }
      //debug
      //for(int i = 0;i<=n;i++){
      //for(int j = 0;j<=n;j++)cout << d[i][j] << ' ';cout << endl;}

      //solve
      fill(solve,solve+n+2,-1);
      que.push(1);
      solve[1] = 0;
      while(!que.empty())
      {
            int p = que.front();
            que.pop();
            for(int i = 1;i<=n;i++)
            {
                  if(d[p][i] && solve[i]==-1)
                  {
                        que.push(i);
                        solve[i] = solve[p] + 1;
                  }
            }
      }
      for(int i = 1;i<=n;i++)
            cout << i << ' '<< solve[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 <iostream>
#include <queue>
#include <vector>
using namespace std;
int d[128][128],solve[128];
int main(){
      int n,m,row,t;
      queue<int> que;
      cin >> n;
      for(int i= 0;i<n;i++){
            cin >>row>>m;
            for(int j = 0;j<m;j++){
                  cin>>t;
                  d[row][t] = 1;
            }
      }
      fill(solve,solve+n+2,-1);
      que.push(1);
      solve[1] = 0;
      while(!que.empty()){
            int p = que.front();
            que.pop();
            for(int i = 1;i<=n;i++){
                  if(d[p][i] && solve[i]==-1){
                        que.push(i);
                        solve[i] = solve[p] + 1;
                  }
            }
      }
      for(int i = 1;i<=n;i++)cout << i << ' '<< solve[i]<<endl;
}