codeforces#P1416E. Split

    ID: 31473 远端评测题 2000ms 256MiB 尝试: 0 已通过: 0 难度: 10 上传者: 标签>binary searchdata structuresdpgreedy*3200

Split

Description

One day, BThero decided to play around with arrays and came up with the following problem:

You are given an array $a$, which consists of $n$ positive integers. The array is numerated $1$ through $n$. You execute the following procedure exactly once:

  • You create a new array $b$ which consists of $2n$ positive integers, where for each $1 \le i \le n$ the condition $b_{2i-1}+b_{2i} = a_i$ holds. For example, for the array $a = [6, 8, 2]$ you can create $b = [2, 4, 4, 4, 1, 1]$.
  • You merge consecutive equal numbers in $b$. For example, $b = [2, 4, 4, 4, 1, 1]$ becomes $b = [2, 4, 1]$.

Find and print the minimum possible value of $|b|$ (size of $b$) which can be achieved at the end of the procedure. It can be shown that under the given constraints there is at least one way to construct $b$.

The first line of the input file contains a single integer $T$ ($1 \le T \le 5 \cdot 10^5$) denoting the number of test cases. The description of $T$ test cases follows.

The first line of each test contains a single integer $n$ ($1 \le n \le 5 \cdot 10^5$).

The second line contains $n$ space-separated integers $a_1$, $a_2$, ..., $a_n$ ($2 \le a_i \le 10^9$).

It is guaranteed that $\sum{n}$ over all test cases does not exceed $5 \cdot 10^5$.

For each test case, print a single line containing one integer — the minimum possible value of $|b|$.

Input

The first line of the input file contains a single integer $T$ ($1 \le T \le 5 \cdot 10^5$) denoting the number of test cases. The description of $T$ test cases follows.

The first line of each test contains a single integer $n$ ($1 \le n \le 5 \cdot 10^5$).

The second line contains $n$ space-separated integers $a_1$, $a_2$, ..., $a_n$ ($2 \le a_i \le 10^9$).

It is guaranteed that $\sum{n}$ over all test cases does not exceed $5 \cdot 10^5$.

Output

For each test case, print a single line containing one integer — the minimum possible value of $|b|$.

Samples

3
3
6 8 2
1
4
3
5 6 6
3
1
2