Count the Number of Triangles in a Graph

Given an undirected graph with v vertices and e edges, you are asked to count the number of triangles in the graph.

A triangle in a graph is a set of 3 vertices that any are all connected to each other.

For instance, the graph in the image has 3 triangles:

1. 1-2-5

2. 2-5-4

3. 3-2-4

Input

The first line of the input contains two integers v (1 ≤ v ≤ 100) and e (1 ≤ e ≤ ).

The following e lines contain pairs of integers v1, v2 (1 ≤ v1, v2 ≤ v) which means that the vertex v1 is connected to the vertex v2 and vice versa.

Output

The program should print the number of triangles in the given graph.

Examples