Go: package main

import "fmt"

type container struct {
	data []int
}

func (c *container) queue(v int) {
	c.data = append(c.data, v)
}
func (c *container) dequeue(p *int) bool {
	if p == nil || len(c.data) == 0 {
		return false
	}
	*p = c.data[0]
	c.data = c.data[1:len(c.data)]
	return true
}

func main() {
	var n int
	fmt.Scan(&n)
	g := make([][]int, n+1) // 1-indexed
	d := make([]int, n+1)   // 1-indexed
	for i := 1; i <= n; i++ {
		d[i] = -1
		var u, k, v int
		fmt.Scan(&u, &k)
		for j := 0; j < k; j++ {
			fmt.Scan(&v)
			g[u] = append(g[u], v)
		}
	}

	var q container
	d[1] = 0
	q.queue(1)

for len(q.data) > 0  { // 幅優先探索
		var v int
		q.dequeue(&v)
		for i := 0; i < len(g[v]); i++ {
			nv := g[v][i]
		if d[nv] == -1 { // 未訪問
				q.queue(nv)
				d[nv] = d[v] + 1
			}
		}
	}
	for i := 1; i <= n; i++ {
		fmt.Printf("%d %d\n", i, d[i])
	}
}

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

using namespace std; 

int main(void) {
	int nov,noe,u,v;
	cin >> nov;
	vector< vector<int> > adj(nov);
	for (int i = 0; i < nov; ++i) {
		cin >> u;
		cin >> noe;
		adj[u-1] = vector<int>(noe);
		for (int j = 0; j < noe; ++j) {
			cin >> adj[u-1][j];
			--adj[u-1][j];
		}
	}
	vector<int> res(nov,-1);
	res[0] = 0;
	queue< pair<int,int> > q;
	q.push({0,0});
	pair<int,int> now;
	while (!q.empty()) {
		now = q.front();
		q.pop();
		for (int i = 0; i < adj[now.first].size(); ++i) {
			if (res[adj[now.first][i]] < 0) {
				res[adj[now.first][i]] = now.second+1;
				q.push({adj[now.first][i],now.second+1});
			}
		}
	}
	for (int i = 0; i < nov; ++i) {
		cout << i+1 << " ";
		cout << res[i] << endl;
	}
	return 0;
}

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

int main(){
	int n,m,l,i,j,p;
	int f[1000][1000];
	int D[1000] = {};
	cin >> n;
	for(i = 0; i < n; i++){
		cin >> m;
		cin >> p;
		for(j = 0; j < p; j++){
			cin >> l;
			f[m][l] = 1;
		}
	}
	queue<int> Q;
	Q.push(1);
	while(!Q.empty()){
		int c = Q.front();
		Q.pop();
		for(i = 2; i <= n; i++){
			if(f[c][i] == 1 && D[i] == 0){
				D[i] = D[c] + 1;
				Q.push(i);
			}
		}
	}				
	for(i = 1; i <= n; i++){
		if (D[i] == 0 && i !=1)
			D[i] = -1;
		cout << i << " " << D[i] << endl;
	}
}

C++: #include <bits/stdc++.h>
using namespace std;
#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)
#define fi first
#define se second
#define mp make_pair
#define itrfor(itr,A) for(auto itr = A.begin(); itr !=A.end();itr++)
template <class T> using reversed_priority_queue = priority_queue<T, vector<T>, greater<T> >;
typedef long long llong;
char moji[26]={'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};
char moji2[26]={'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
char moji3[10]={'0','1','2','3','4','5','6','7','8','9'};
#define Sort(a) sort(a.begin(),a.end());
#define Reverse(a) reverse(a.begin(),a.end());
#define print(a) cout << a << endl;
#define MOD llong(1e9+7)
#define MAX int(2 * 1e5 +5)
#define debug(x)  cout << #x << " = " << (x) << endl;
#define pi acos(-1.0)
#define int llong
#define INF llong(1e18 + 3)
template<class T> bool chmax(T &a,  T b) {if(a<b){a=b; return 1;} return 0;}
template<class T> bool chmin(T &a,  T b) {if(a>b){a=b; return 1;} return 0;}
bool Add(int &a,int b){a = (a + b) % MOD;}
void myprint(int* A,int A_num){
   REP(i,A_num) cout << A[i] << " ";
   cout << endl;
}



signed main(){
    int n;
    cin >> n;
    int dist[n];
    vector<int> G[n];
    REP(i,n) dist[i] = -1;
    REP(i,n){
        int v,k;
        cin >> v >> k;
        REP(j,k){
            int to;
            cin >> to;
            to --;
            G[i].push_back(to);
        }
    }

    queue<int> Q;
    dist[0] = 0;
    Q.push(0);
    while(Q.size()){
        int v = Q.front();
        Q.pop();
        itrfor(itr,G[v]){
            if(dist[*itr] ==  -1){
                Q.push(*itr);
                dist[*itr] = dist[v] + 1;
            }
        }
    }
    REP(i,n){
        cout << i + 1 << " " << dist[i] << endl;
    }

}

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

using namespace std;

struct Node {
    bool visit = false;
    vector<int> next;
    int d = -1;
};

int main() {
    int n, id, k, temp;
    Node node[101];
    queue<int> que;
    
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> id >> k;
        for (int j = 0; j < k; j++) {
            cin >> temp;
            node[id].next.push_back(temp);
        }
    }

    node[1].d = 0;
    node[1].visit = true;
    que.push(1);
    while (!que.empty()) {
        temp = que.front();
        for (int i = 0; i < node[temp].next.size(); i++) {
            if (node[node[temp].next[i]].visit == false) {
                node[node[temp].next[i]].d = node[temp].d + 1;
                node[node[temp].next[i]].visit = true;
                que.push(node[temp].next[i]);
            }
        }
        que.pop();
    }

    for (int i = 1; i <= n; i++) {
        cout << i << " " << node[i].d << endl;
    }
    
    return 0;
}

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

const int INF = 0x3f3f3f3f;
int t1, t2, t3, n, e[105][105];

int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= n; j++) e[i][j] = INF;
		e[i][i] = 0;
	}
	for (int i = 0; i < n; i++) {
		cin >> t1 >> t2;
		for (int j = 0; j < t2; j++) {
			cin >> t3;
			e[t1][t3] = 1;
		}
	}
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= n; j++) {
			for (int k = 1; k <= n; k++) {
				e[j][k] = min(e[j][k], e[j][i] + e[i][k]);
			}
		}
	}
	for (int i = 1; i <= n; i++) {
		cout << i << ' ' << ((e[1][i] == INF) ? -1 : e[1][i]) << endl;
	}
}

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

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

int d[N] = {0};

void bfs(int M[N][N], int n, 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 n;
    cin >> n;

    int M[N][N] = {0};
    int u, k, v;
    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(M, n, 0);

    return 0;
}