bzoj3545 Peaks 线段树合并
离线乱搞。。。
也就是一个线段树合并没什么
#include<algorithm>
#include<iostream>
#include<cstring>
#include<cstdio>
using namespace std;
int n,m,q,tot,cnt,num,h[100001],a[100001],ans[500001],fa[100001],root[100001];
struct edge{
int u,v,cost;
bool operator < (const edge &b) const{
return cost<b.cost;
}
}e[500001];
struct Que{
int id,v,x,k;
bool operator < (const Que &b) const{
return x<b.x;
}
}que[500001];
struct node{
int lch,rch,siz;
}tree[2000001];
int find(int x){
if(fa[x]==x)return x;
return fa[x]=find(fa[x]);
}
void insert(int o,int l,int r,int x){
tree[o].siz++;
if(l==r)return;
int mid=(l+r)>>1;
if(x<=mid){
if(!tree[o].lch)tree[o].lch=++num;
insert(tree[o].lch,l,mid,x);
}
if(x>mid){
if(!tree[o].rch)tree[o].rch=++num;
insert(tree[o].rch,mid+1,r,x);
}
}
int query(int o,int l,int r,int k){
if(k<=0 or k>tree[o].siz)return -1;
if(l==r)return l;
int mid=(l+r)>>1;
if(k<=tree[tree[o].lch].siz)return query(tree[o].lch,l,mid,k);
return query(tree[o].rch,mid+1,r,k-tree[tree[o].lch].siz);
}
int merge(int x,int y){
if(!x or !y)return x+y;
tree[x].siz+=tree[y].siz;
tree[x].lch=merge(tree[x].lch,tree[y].lch);tree[x].rch=merge(tree[x].rch,tree[y].rch);
return x;
}
int main(){
scanf("%d%d%d",&n,&m,&q);
for(int i=1;i<=n;i++){
scanf("%d",&h[i]);
a[i]=h[i];fa[i]=i;
}
sort(a+1,a+n+1);
for(int i=1;i<=n;i++)h[i]=lower_bound(a+1,a+n+1,h[i])-a;
for(int i=1;i<=m;i++){
scanf("%d%d%d",&e[i].u,&e[i].v,&e[i].cost);
}
sort(e+1,e+m+1);
for(int i=1;i<=q;i++){
scanf("%d%d%d",&que[i].v,&que[i].x,&que[i].k);que[i].id=i;
}
for(int i=1;i<=n;i++){
fa[i]=i;
root[i]=++num;
insert(root[i],1,n,h[i]);
}
sort(que+1,que+q+1);
for(int i=1;i<=q;i++){
while(cnt<m and e[cnt+1].cost<=que[i].x){
int fx=find(e[++cnt].u);
int fy=find(e[cnt].v);
if(fx==fy)continue;
fa[fx]=fy;
root[fy]=merge(root[fx],root[fy]);
}
int rot=root[find(que[i].v)],ret=query(rot,1,n,tree[rot].siz-que[i].k+1);
ans[que[i].id]=~ret?a[ret]:ret;
}
for(int i=1;i<=q;i++){
printf("%d\n",ans[i]);
}
return 0;
}