#P14619. [2019 KAIST RUN Fall] Maximizer

[2019 KAIST RUN Fall] Maximizer

题目描述

Maximizer has two permutations A=[a1,a2,,aN]A=[a_1,a_2,\cdots,a_N] and B=[b1,b2,,bN]B=[b_1,b_2,\cdots,b_N]. Both A,BA, B have length NN and consists of distinct integers\textbf{distinct integers} from 11 to NN.

Maximizer wants to maximize the sum of differences of each element, i=1Naibi\sum_{i=1}^{N} |a_i - b_i|. But he can only swap two adjacent elements in AA. Precisely, he can only swap aia_i and ai+1a_{i+1} for some ii from 11 to N1N-1. He can swap as many times as he wants.

What is the minimum number of swaps required for maximizing the difference sum?

输入格式

The first line contains an integer NN. (1N2500001 \leq N \leq 250 000)

The second line contains NN integers a1,a2,,aNa_1,a_2,\cdots,a_N (1aiN1 \leq a_i \leq N).

The third line contains NN integers b1,b2,,bNb_1,b_2,\cdots,b_N (1biN1 \leq b_i \leq N).

Each of [a1,a2,,aN][a_1,a_2,\cdots,a_N] and [b1,b2,,bN][b_1,b_2,\cdots,b_N] is a permutation. In other words, it is consisted of distinct integers from 11 to NN.

输出格式

Print an integer, the minimum number of swaps required for maximizing the difference sum.

3
1 2 3
1 2 3
2
4
3 4 1 2
3 2 4 1
3