## Wesley's Anger Contest Reject 1 - Stupendous Bowties 2

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Points: 17
Time limit: 2.0s
Memory limit: 256M

Author:
Problem types

A Fantastic Right Triangle is a subgraph which uses distinct vertices and distinct edges, such that each pair of vertices has exactly edge connecting them.

A Stupendous Bowtie consists of an unordered pair of Fantastic Right Triangles which share exactly one vertex. Count the number of Stupendous Bowties in the given graph with vertices and edges.

Below is an example of a Stupendous Bowtie:

#### Constraints

For this problem, you will be required to pass all the samples in order to receive points.

and each pair of distinct vertices are connected by at most one edge.

#### Input Specification

The first line contains two space-separated integers and .

lines follow; the one contains two space-separated integers indicating that vertices and are connected by an edge.

#### Output Specification

This problem is graded with an identical checker. This includes whitespace characters. Ensure that every line of output is terminated with a \n character and that there are no trailing spaces.

Output the number of Stupendous Bowties in the given graph on a single line.

#### Sample Input 1

5 6
1 2
2 3
3 1
3 4
3 5
4 5

#### Sample Output 1

1

#### Sample Input 2

5 10
1 2
1 3
1 4
1 5
2 3
2 4
2 5
3 4
3 5
4 5

#### Sample Output 2

15