Oneline with 3 < = N < = 10000{the number of nodes{and N < = M < = 2N {the number
of edges.
N lines with the x and y coordinates o feachnode,inorder.0 < = x;y < = 10000.The nodes
have unique coordinate pairs.
M lines with two space separated numbers i and j,denoting an edge between nodes i and
j.The nodes are 0-indexed.
第一行 两个数,N , M . (3<=N <=10000, 代表结点的个数。N<=M<=2N 边的个数)
接下来N行，依次组出每个结点的坐标 0<=x,y<=10000 。每个结点的坐标是唯一 的
接下来M行,每两个数，表示i, j之间存在一条边.(结点从0开始编号)