4991 - [Usaco2017 Feb]Why Did the Cow Cross the Road III

Farmer John is continuing to ponder the issue of cows crossing the road through his farm, introduced in the preceding two problems. He realizes now that the threshold for friendliness is a bit more su btle than he previously considered -- breeds aa and bb are now friendly if |a-b|≤K, and unfriendly otherwise.Given the orderings of fields on either side of the road through FJ's farm, please count t he number of unfriendly crossing pairs of breeds, where a crossing pair of breeds is defined as in t he preceding problems. 思考过前两个问题后，农民约翰正在继续思考如何对付穿过农场的牛的问题。 他现在意识到，友好的品种的标准 比他以前想的稍微微妙一些 -对于品种a,b，如果|a - b|≤K，现在是友好的。 否则是不友好的。给定这条路两边 的田地的顺序，请计算有多少交叉的不良品种对，其中一对品种在前问题被定义。

The first line of input contains N (1≤N≤100,000) and K (0≤K<N). The next N lines describe the order, by breed ID, of fields on one side of the road; each breed ID is an integer in the range 1…N. The last N lines describe the order, by breed ID, of the fields on the other side of the road. Each breed ID appears exactly once in each ordering.

Please output the number of unfriendly crossing pairs of breeds.