D. Pair of Topics

链接：https://codeforces.ml/contest/1324/problem/D

The next lecture in a high school requires two topics to be discussed. The ii-th topic is interesting by aiai units for the teacher and by bibi units for the students.

The pair of topics ii and jj (ibi+bjai+aj>bi+bj (i.e. it is more interesting for the teacher).

Your task is to find the number of good pairs of topics.

Input

The first line of the input contains one integer nn (2≤n≤2⋅1052≤n≤2⋅105) — the number of topics.

The second line of the input contains nn integers a1,a2,…,ana1,a2,…,an (1≤ai≤1091≤ai≤109), where aiai is the interestingness of the ii-th topic for the teacher.

The third line of the input contains nn integers b1,b2,…,bnb1,b2,…,bn (1≤bi≤1091≤bi≤109), where bibi is the interestingness of the ii-th topic for the students.

Output

Print one integer — the number of good pairs of topic.

Examples

input

Copy

5
4 8 2 6 2
4 5 4 1 3

output

Copy

7

input

Copy

4
1 3 2 4
1 3 2 4

output

Copy

0

代码：

#include
using namespace std;
long long  n,k,ans;
long long a[200005],b[200005];
vectorc,d;
int main()
{cin>>n;for(int i=1;i<=n;i++){cin>>a[i];}for(int i=1;i<=n;i++){cin>>b[i];a[i]-=b[i];}for(int i=1;i<=n;i++){if(a[i]>0)c.push_back(a[i]);elsed.push_back(a[i]);} sort(c.begin(),c.end());sort(d.rbegin(),d.rend());int j=0;ans=0;for(int i=0;i0)j++;ans+=j;}ans+=((long long)c.size()*(c.size()-1))/2;	cout<

本文来自互联网用户投稿，文章观点仅代表作者本人，不代表本站立场，不承担相关法律责任。如若转载，请注明出处。 如若内容造成侵权/违法违规/事实不符，请点击【内容举报】进行投诉反馈！