The member states of the UN are planning to send $2$ people to the moon. They want them to be from different countries. You will be given a list of pairs of astronaut ID's. Each pair is made of astronauts from the same country. Determine how many pairs of astronauts from different countries they can choose from.

Example

$n=4$

$astronaut=[1,2],[2,3]$

There are $\begin{array}{c}4\end{array}$ astronauts numbered $\mbox{0}$ through $3$. Astronauts grouped by country are $\left[\mbox{0}\right]$ and $[1,2,3]$. There are $3$ pairs to choose from: $[0,1],[0,2]$ and $[0,3]$.

Function Description

Complete the journeyToMoon function in the editor below.

journeyToMoon has the following parameter(s):

int n: the number of astronauts
int astronaut[p][2]: each element $\textit{astronaut}[i]$ is a $2$ element array that represents the ID's of two astronauts from the same country

Returns

• int: the number of valid pairs

Input Format

The first line contains two integers $n$ and $\boldsymbol{p}$, the number of astronauts and the number of pairs.

Each of the next $\boldsymbol{p}$ lines contains $2$ space-separated integers denoting astronaut ID's of two who share the same nationality.

Constraints

$1\leq n\leq10^5$
$1\leq p\leq10^4$

Sample Input 0
5 3
0 1
2 3
0 4

Sample Output 0
6

Explanation 0

Persons numbered $[0,1,4]$ belong to one country, and those numbered $[2,3]$ belong to another. The UN has $\boldsymbol{6}$ ways of choosing a pair:

$[0,2],[0,3],[1,2],[1,3],[4,2],[4,3]$

Sample Input 1
4 1
0 2

Sample Output 1
5

Explanation 1

Persons numbered $[0,2]$ belong to the same country, but persons $\mbox{1}$ and $3$ don't share countries with anyone else. The UN has $5$ ways of choosing a pair:

$[0,1],[0,3],[1,2],[1,3],[2,3]$

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