摘要：题意 description You are given an array a1,a2,...,an(∀i∈[1,n],1≤ai≤n). Initially, each element of the array is unique . Moreover, there are m instructio 阅读全文

摘要：``` include include include int const maxn = 200010; using namespace std; int a[maxn], b[maxn]; //第几个版本的根节点编号 int root[maxn 1; build(lc[rt], l, mid); 阅读全文