codeforces#P1883E. Look Back
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Description
You are given an array of integers $a_1, a_2, \ldots, a_n$. You need to make it non-decreasing with the minimum number of operations. In one operation, you do the following:
- Choose an index $1 \leq i \leq n$,
- Set $a_i = a_i \cdot 2$.
An array $b_1, b_2, \ldots, b_n$ is non-decreasing if $b_i \leq b_{i+1}$ for all $1 \leq i < n$.
Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases. This is followed by their description.
The first line of each test case contains an integer $n$ ($1 \leq n \leq 10^5$) — the size of the array $a$.
The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq 10^9$).
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
For each test case, output the minimum number of operations needed to make the array non-decreasing.
Input
Each test consists of multiple test cases. The first line contains a single integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases. This is followed by their description.
The first line of each test case contains an integer $n$ ($1 \leq n \leq 10^5$) — the size of the array $a$.
The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq 10^9$).
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
Output
For each test case, output the minimum number of operations needed to make the array non-decreasing.
9
1
1
2
2 1
3
3 2 1
4
7 1 5 3
5
11 2 15 7 10
6
1 8 2 16 8 16
2
624323799 708290323
12
2 1 1 3 3 11 12 22 45 777 777 1500
12
12 11 10 9 8 7 6 5 4 3 2 1
0
1
3
6
10
3
0
2
66
Note
No operations are needed in the first test case.
In the second test case, we need to choose $i = 2$, after which the array will be $[2, 2]$.
In the third test case, we can apply the following operations:
- Choose $i = 3$, after which the array will be $[3, 2, 2]$,
- Choose $i = 3$, after which the array will be $[3, 2, 4]$,
- Choose $i = 2$, after which the array will be $[3, 4, 4]$.