You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in python3.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```python
<your code here>
```

Execution time limit: 2.0 seconds
Memory limit: 256.0 MB

# Problem
You are given two lists of segments $$$[al_1, ar_1], [al_2, ar_2], \dots, [al_n, ar_n]$$$ and $$$[bl_1, br_1], [bl_2, br_2], \dots, [bl_n, br_n]$$$.

Initially, all segments $$$[al_i, ar_i]$$$ are equal to $$$[l_1, r_1]$$$ and all segments $$$[bl_i, br_i]$$$ are equal to $$$[l_2, r_2]$$$.

In one step, you can choose one segment (either from the first or from the second list) and extend it by $$$1$$$. In other words, suppose you've chosen segment $$$[x, y]$$$ then you can transform it either into $$$[x - 1, y]$$$ or into $$$[x, y + 1]$$$.

Let's define a total intersection $$$I$$$ as the sum of lengths of intersections of the corresponding pairs of segments, i.e. $$$\sum\limits_{i=1}^{n}{\text{intersection_length}([al_i, ar_i], [bl_i, br_i])}$$$. Empty intersection has length $$$0$$$ and length of a segment $$$[x, y]$$$ is equal to $$$y - x$$$.

What is the minimum number of steps you need to make $$$I$$$ greater or equal to $$$k$$$?

## Input Format
The first line contains the single integer $$$t$$$ ($$$1 \le t \le 1000$$$) — the number of test cases.

The first line of each test case contains two integers $$$n$$$ and $$$k$$$ ($$$1 \le n \le 2 \cdot 10^5$$$; $$$1 \le k \le 10^9$$$) — the length of lists and the minimum required total intersection.

The second line of each test case contains two integers $$$l_1$$$ and $$$r_1$$$ ($$$1 \le l_1 \le r_1 \le 10^9$$$) — the segment all $$$[al_i, ar_i]$$$ are equal to initially.

The third line of each test case contains two integers $$$l_2$$$ and $$$r_2$$$ ($$$1 \le l_2 \le r_2 \le 10^9$$$) — the segment all $$$[bl_i, br_i]$$$ are equal to initially.

It's guaranteed that the sum of $$$n$$$ doesn't exceed $$$2 \cdot 10^5$$$.

## Output Format
Print $$$t$$$ integers — one per test case. For each test case, print the minimum number of step you need to make $$$I$$$ greater or equal to $$$k$$$.

## Examples
```input
3
3 5
1 2
3 4
2 1000000000
1 1
999999999 999999999
10 3
5 10
7 8
```
```output
7
2000000000
0
```

## Note
In the first test case, we can achieve total intersection $$$5$$$, for example, using next strategy:

- make $$$[al_1, ar_1]$$$ from $$$[1, 2]$$$ to $$$[1, 4]$$$ in $$$2$$$ steps;
- make $$$[al_2, ar_2]$$$ from $$$[1, 2]$$$ to $$$[1, 3]$$$ in $$$1$$$ step;
- make $$$[bl_1, br_1]$$$ from $$$[3, 4]$$$ to $$$[1, 4]$$$ in $$$2$$$ steps;
- make $$$[bl_2, br_2]$$$ from $$$[3, 4]$$$ to $$$[1, 4]$$$ in $$$2$$$ steps.

In the second test case, we can make $$$[al_1, ar_1] = [0, 1000000000]$$$ in $$$1000000000$$$ steps and $$$[bl_1, br_1] = [0, 1000000000]$$$ in $$$1000000000$$$ steps.

In the third test case, the total intersection $$$I$$$ is already equal to $$$10 > 3$$$, so we don't need to do any steps.

Now solve the problem and return the code.