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Breadth First Search

Write a program which reads an directed graph G=(V,E), and finds the shortest distance from vertex 1 to each vertex (the number of edges in the shortest path). Vertices are identified by IDs 1,2,...n.

Input

In the first line, an integer n denoting the number of vertices, is given. In the next n lines, adjacent lists of vertex u are given in the following format:

u k v1 v2 ... vk

u is ID of the vertex and k denotes its degree.vi are IDs of vertices adjacent to u.

Constraints

Output

For each vertex u, print id and d in a line. id is ID of vertex u and d is the distance from vertex 1 to vertex u. If there are no path from vertex 1 to vertex u, print -1 as the shortest distance. Print in order of IDs.

Sample Input 1

4
1 2 2 4
2 1 4
3 0
4 1 3

Sample Output 1

1 0
2 1
3 2
4 1

Reference

Introduction to Algorithms, Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Clifford Stein. The MIT Press.