原题链接题解正着来发现很怪，倒着来发现顺多了code#include<bits/stdc++.h>#definelllonglongusingnamespacestd;constllN=114514;lltree[8*N]={0};lltag[8*N]={0};stringa,b;voidbuild(intnode,intl,intr){tag[node]=-1;if(l==r){

原题链接真恶心code#include<bits/stdc++.h>#definelllonglongusingnamespacestd;constllN=114514;lla[200005],d[200005];boolsolve(){lln;cin>>n;for(lli=1;i<=2*n;i++)cin>>d[i];sort(d+1,d+1+2*n);for(i