Cross Count

There is a Cartesian plane with N vertical lines (infinitely long), and M line segments (finite).
Your task is to count the total number of crossings made by the finite line segments, with the infinitely long vertical lines.

Example: There are N = 4 infinitely long vertical lines, at

There are M = 8 finite line segments:

\({(-2,\ \ \ 5),(\ \ \ 5,-6)}\)
\({(-5,-2),(-3,-5)}\)
\({(-2,\ \ \ 3),(-6,\ \ \ 1)}\)
\({(-1,-3),(\ \ \ 4,\ \ \ 2)}\)
\({(\ \ \ 2,\ \ \ 5),(\ \ \ 2,\ \ \ 1)}\)
\({(\ \ \ 4,\ \ \ 5),(\ \ \ 4,-5)}\)
\({(-2,-4),(\ \ \ 5,\ \ \ 3)}\)
\({(\ \ \ 1,\ \ \ 2),(-2,\ \ \ 1)}\)

After marking the infinitely long vertical lines and the line segments, the Cartesian plane looks like this.

The circles denote the crossings. Black circles denote 1 crossing. Red circles denote 2 crossings. So the answer is 8.

Input Format

First line contains two integers, N and M.
Second line contains N space separated integers, with i^th of them indicating X_i, the x coordinate of the i^th infinitely long vertical line.
M lines follow, each containing 4 space separated integers, x₁, y₁, x₂, y₂, The start and end points of the line segments.

Output Format

A single integer, denoting the total number of crossings between the infinitely long vertical lines and the line segments.

Notes

• The output might not fit into Integer data type.
• For contestants using C++ or Java, you might need to use faster I/O techniques. (Refer: C++ / Java)

Constraints

• 1 \(\leq\) n, m \(\leq\) 10⁶
• -10⁶ \(\leq\) X_i, x₁, y₁, x₂, y₂ \(\leq\) 10⁶

Limits

• Time Limit: 2s
• Memory Limit: 256MB

Sample Input 0

4 8
-5 -3 2 3
-2 5 5 -6
-5 -2 -3 -5
-2 3 -6 1
-1 -3 4 2
2 5 2 1
4 5 4 -5
-2 -4 5 3
1 2 -2 1

Sample Output 0

8