A15000. Unequal Array

You are given an array $a$ of length $n$ . We define the equality of the array as the number of indices $1 \le i \le n - 1$ such that $a_i = a_{i + 1}$ . We are allowed to do the following operation:

- Select two integers $i$ and $x$ such that $1 \le i \le n - 1$ and $1 \le x \le 10^9$ . Then, set $a_i$ and $a_{i + 1}$ to be equal to $x$ .

Find the minimum number of operations needed such that the equality of the array is less than or equal to $1$ .

Each test contains multiple test cases. The first line contains a single integer $t$ ( $1 \leq t \leq 10^4$ ) — the number of test cases. The description of the test cases follows.

The first line of each test case contains an integer $n$ ( $2 \le n \le 2 \cdot 10 ^ 5$ ) — the length of array $a$ .

The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ( $1 \le a_i \le 10^9$ ) — elements of the array.

It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10 ^ 5$

For each test case, print the minimum number of operations needed.

In the first test case, we can select $i=2$ and $x=2$ to form $[1, 2, 2, 1, 1]$ . Then, we can select $i=3$ and $x=3$ to form $[1, 2, 3, 3, 1]$ .

In the second test case, we can select $i=3$ and $x=100$ to form $[2, 1, 100, 100, 2]$ .