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# 1319. Number of Operations to Make Network Connected

## Description

There are `n`

computers numbered from `0`

to `n - 1`

connected by ethernet cables `connections`

forming a network where `connections[i] = [a`

represents a connection between computers _{i}, b_{i}]`a`

and _{i}`b`

. Any computer can reach any other computer directly or indirectly through the network._{i}

You are given an initial computer network `connections`

. You can extract certain cables between two directly connected computers, and place them between any pair of disconnected computers to make them directly connected.

Return *the minimum number of times you need to do this in order to make all the computers connected*. If it is not possible, return `-1`

.

**Example 1:**

Input:n = 4, connections = [[0,1],[0,2],[1,2]]Output:1Explanation:Remove cable between computer 1 and 2 and place between computers 1 and 3.

**Example 2:**

Input:n = 6, connections = [[0,1],[0,2],[0,3],[1,2],[1,3]]Output:2

**Example 3:**

Input:n = 6, connections = [[0,1],[0,2],[0,3],[1,2]]Output:-1Explanation:There are not enough cables.

**Constraints:**

`1 <= n <= 10`

^{5}`1 <= connections.length <= min(n * (n - 1) / 2, 10`

^{5})`connections[i].length == 2`

`0 <= a`

_{i}, b_{i}< n`a`

_{i}!= b_{i}- There are no repeated connections.
- No two computers are connected by more than one cable.