Splitting peas are a remarkable phenomenon. Every so often they
all jump up and split themselves in two. Now imagine a straight line of
cups, each one containing a certain number of splitting peas. To the left
of the line of cups, there is a wall (we will get back to it later). When
it is splitting time, all the peas jump up out of their cups, and split
themselves in mid-air. From each split pea, the two resulting peas land
in the two neighboring cups (one in each cup).

An example:

In this configuration we have five cups, and one pea in the center cup. We will denote this configuration as (0,0,1,0,0).

After one step (i.e. one splitting of the peas), we get the following configuration (0,1,0,1,0):

One step later the configuration is (1,0,2,0,1), we leave it up to you to draw this one if you like.

In the third step, however, some interesting things happen, since there are peas in the leftmost cup and in the rightmost cup.

The peas in the leftmost cup jump up, split, and one pea will go to
the second cup from the left (as usual), but the other pea will bounce
against the wall and land in the leftmost cup again. The peas in the rightmost
cup will also jump up, split, and one pea will go to the second cup from
the right (as usual), but the other pea will fall off the right side of
the table and disappear. So the configuration after the next step will
be (1,3,0,3,0). Another example is the configuration (1,2,3,4,5), which
becomes (3,4,6,8,4) in one step. We say that the predecessor of (3,4,6,8,4)
is (1,2,3,4,5). Most configurations have a predecessor (which is always
unique), some configurations however, do not have a predecessor: these
configurations are called root configurations. In the first example we
gave, (0,0,1,0,0) is obviously a root configuration, and in our second
example (1,2,3,4,5) is also a root configuration.

**The problem**

You are given a configuration that resulted after a certain number of steps from some root configuration. It is up to you to calculate the number of steps that took place, in going from the unknown root configuration to the given input configuration.

**Input**

The first line of the input contains the number of runs R (1 <= R <= 10,000). For each run there is one line containing the number of cups p (2 <= p <= 1,000), followed by one line containing p integers ni (0 <= ni <= 1,000,000), representing the number of peas in cup i (from left to right).

**Output**

For each run, the output should consist of one line containing the number of steps that have been taken to reach the given input configuration from a root configuration.

**Sample Input**

3

5

1 3 0 3 0

5

3 4 6 8 4

3

7 0 7

**Sample Output**

3

1

2