## Problem

A directed graph is *semi-connected* if for all pairs of vertices $i,j$ there is either a path from
$i$ to $j$ or a path from $j$ to $i$.

Given: A positive integer $k \le 20$ and $k$ simple directed graphs with at most $10^3$ vertices each in the edge list format.

Return: For each graph, output "1" if the graph is semi-connected and "-1" otherwise.

## Sample Dataset

2
3 2
3 2
2 1
3 2
3 2
1 2

## Sample Output

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