B"You are given an undirected graph of N nodes and M edges, E_1, E_2, ... E_M . A connected graph is a cactus if each of it's edges belogs to at most one simple cycle. A graph is a desert if each of it's connected components is a cactus. Find the number of pairs (L, R) , ( 1 <= q L <= q R <= q M ) such that, if we delete all the edges except for E_L, E_{L+1}, ... E_R , the graph is a desert. The first line contains two integers N and M ( 2 <= q N <= q 2.5 x 10^5 , 1 <= q M <= q 5 x 10^5 ). Each of the next M lines contains two integers. The i -th line describes the i -th edge. It contains integers U_i and V_i , the nodes connected by the i -th edge ( E_i=(U_i, V_i) ). It is guaranteed that 1 <= q U_i, V_i <= q N and U_i neq V_i . The output contains one integer number xe2 x80 x93 the answer. In the second example: Graphs for pairs (1, 1) , (2, 2) and (3, 3) are deserts because they don't have any cycles. Graphs for pairs (1, 2) and (2, 3) have one cycle of length 2 so they are deserts. "...