# Wireless Signal

Criterion 2022 Round 15
Limits 1s, 256 MB

The city of Byteland is rectangular in shape and can be represented as a 2D coordinate system with $n$ columns and $m$ rows. At each of the intersections, there is a house. The top left house of the city is situated at coordinate $(0, m-1)$ and the bottom right house is situated at $(n-1, 0)$. The town hall is situated at the coordinate $(x, y)$ which contains a cell tower providing wireless network signal to all the houses in Byteland. Judges will be moving to Byteland soon. Wireless signal travels in a straight line and it gets weakened only if the signal has to travel straight through another house, judges want to choose a house in such a way that their devices receive maximum possible signal strength.

Can you tell me how many different houses meet judges’ requirements?

Note: Judges can not move to the town hall as the mayor lives there. The width and length of the houses are so small that you can ignore them.

## Input

The first line of the input will contain a single integer $T(1 \leq T \leq 10^6)$, denoting the number of test cases.

The next $T$ lines will contain four integers $n, m, x, y(1 \leq n,m \leq 10^6; 0 \leq x < n; 0 \leq y < m)$ each.

It is guaranteed that sum of $max(n,m)$ in all the test cases doesn’t exceed $10^7.$

## Output

For each test case, print an integer containing the answer.

## Sample

InputOutput
3
1 1 0 0
2 3 1 1
4 4 1 1

0
5
12


In the first case, there are no houses available.

In the second case, all houses but the town hall meets the requirements. In the third case, 12 houses meet the requirements