Mark is cleaning a row of $n$ rooms. The $i$-th room has a nonnegative dust level $a_i$. He has a magical cleaning machine that can do the following three-step operation.
- Select two indices
$i \lt j$such that the dust levels$a_i$,$a_{i+1}$,$\dots$,$a_{j-1}$are all strictly greater than$0$. - Set
$a_i$to$a_i-1$. - Set
$a_j$to$a_j+1$.
Mark's goal is to make $a_1 = a_2 = \ldots = a_{n-1} = 0$ so that he can nicely sweep the $n$-th room. Determine the minimum number of operations needed to reach his goal.
Input
The first line contains a single integer $t$ ($1\leq t\leq 10^4$) — the number of test cases.
The first line of each test case contains a single integer $n$ ($2\leq n\leq 2\cdot 10^5$) — the number of rooms.
The second line of each test case contains $n$ integers $a_1$, $a_2$, ..., $a_n$ ($0\leq a_i\leq 10^9$) — the dust level of each room.
It is guaranteed that the sum of $n$ across all test cases does not exceed $2\cdot 10^5$.
Output
For each test case, print a line containing a single integer — the minimum number of operations. It can be proven that there is a sequence of operations that meets the goal.
Note
In the first case, one possible sequence of operations is as follows.
- Choose
$i=1$and$j=2$, yielding the array$[1,1,0]$. - Choose
$i=1$and$j=3$, yielding the array$[0,1,1]$. - Choose
$i=2$and$j=3$, yielding the array$[0,0,2]$.
At this point, $a_1=a_2=0$, completing the process.
In the second case, one possible sequence of operations is as follows.
- Choose
$i=4$and$j=5$, yielding the array$[0,2,0,1,1]$. - Choose
$i=2$and$j=3$, yielding the array$[0,1,1,1,1]$. - Choose
$i=2$and$j=5$, yielding the array$[0,0,1,1,2]$. - Choose
$i=3$and$j=5$, yielding the array$[0,0,0,1,3]$. - Choose
$i=4$and$j=5$, yielding the array$[0,0,0,0,4]$.
In the last case, the array already satisfies the condition.
样例
4
3
2 0 0
5
0 2 0 2 0
6
2 0 3 0 4 6
4
0 0 0 10
3
5
11
0
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