Given a graph having $$N$$ vertices and an array $$A$$ of $$M$$ undirected edges, find the number of pairs of indices $$(l,r), 1 \le l \le r \le M$$, in $$A$$, such that if we consider edges only from $$A[l], A[l+1], ... ,A[r]$$, then the graph is connected.
First line consists of two space separated integers denoting $$N$$ and $$M$$.
Following $$M$$ lines consists of two space separated $$u$$ and $$v$$, denoting an undirected edge.
Print the required answer.
$$1 \le N, M \le 10^5$$
$$1 \le u, v \le N$$