Just Shortest Distance Peoblem - BFS

#include<bits/stdc++.h>
const int N = 1050;
using namespace std;
int n, m;
int dist[N];
vector<int> g[N];
void update(int v)
{
	for (int i = 0; i < g[v].size(); i++)
	{
		int to = g[v][i];
		if (dist[to]>dist[v] + 1)
		{
			dist[to] = dist[v] + 1;
			update(to);
		}
	}
}
int main(){
	ios_base::sync_with_stdio(0);
	cin >> n >> m;
	for (int i = 2; i <= n; i++)
		dist[i] = 1e9;
	for (int i = 1; i <= m; i++)
	{
		int tp;
		cin >> tp;
		if (tp == 1)
		{
			int x;
			cin >> x;
			if (dist[x] > 1e8)
				cout << -1 << endl;
			else
				cout << dist[x] << endl;
		}
		if (tp == 2)
		{
			int a, b;
			cin >> a >> b;
			g[a].push_back(b);
			if (dist[b] > dist[a] + 1)
			{
				dist[b] = dist[a] + 1;
				update(b);
			}
		}
	}
	return 0;
}