mirror of
https://github.com/Kiritow/OJ-Problems-Source.git
synced 2024-03-22 13:11:29 +08:00
113 lines
2.9 KiB
C++
113 lines
2.9 KiB
C++
#include<iostream>
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#include<cstdio>
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#include<cstring>
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#include<algorithm>
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#include<set>
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using namespace std;
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struct line{
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int l,r;
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};
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bool operator < (const line &a,const line &b)
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{
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if(a.r<b.r)return 1;
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if(a.r==b.r){
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if(a.l<b.l)return 1;
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}
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return 0;
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}
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line L[100005];
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int pos[200005];
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int d[400005];
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int maxv[400005];
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int yl,yr;
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void maintain(int o,int l,int r)
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{
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int lc=o*2;
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int rc=o*2+1;
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if(r>l){
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maxv[o]=max(maxv[lc],maxv[rc]);
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}else maxv[o]=0;
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maxv[o]+=d[o];
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}
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void update(int o,int l,int r)
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{
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int lc=o*2;
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int rc=o*2+1;
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if(yl<=l&&yr>=r){
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d[o]++;
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} else {
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int mid=l+((r-l)>>1);
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if(yl<=mid)update(lc,l,mid);
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if(yr>mid)update(rc,mid+1,r);
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}
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maintain(o,l,r);
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}
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int query(int o,int l,int r,int add)
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{
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if(yl<=l&&yr>=r){
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return maxv[o]+add;
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} else {
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int m=l+((r-l)>>1);
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int ret=-1;
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if(yl<=m)ret=max(ret,query(o*2 , l , m , add + d[o] ) );
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if(yr>m)ret=max(ret , query(o*2+1 , m+1 , r , add+d[o]));
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return ret;
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}
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}
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int bisearch(int x,int tot)
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{
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int le=0;
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int ri=tot-1;
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while(le<ri){
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int mid=(le+ri)>>1;
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if(pos[mid]==x)return mid;
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if(pos[mid]>x)ri=mid-1;
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else {
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le=mid+1;
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}
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}
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return le;
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}
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int main()
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{
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int T;
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scanf("%d",&T);
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while(T--){
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int n;
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scanf("%d",&n);
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int tot=0;
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set<int> s;
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s.clear();
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for(int i=0;i<n;++i){
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scanf("%d%d",&L[i].l,&L[i].r);
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if(s.find(L[i].l)==s.end()){
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s.insert(L[i].l);
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pos[tot++]=L[i].l;
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}
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if(s.find(L[i].r)==s.end()){
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s.insert(L[i].r);
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pos[tot++]=L[i].r;
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}
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}
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sort(pos,pos+tot);
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for(int i=0;i<=tot*4;++i){
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d[i]=0;
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maxv[i]=0;
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}
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int ans=0;
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for(int i=0;i<n;++i){
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int le=bisearch(L[i].l,tot);
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int ri=bisearch(L[i].r,tot);
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le++;
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ri++;
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yl=le;
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yr=ri;
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update(1,1,tot);
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}
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yl=1;yr=tot;
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ans=query(1,1,tot,0);
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printf("%d\n",ans);
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}
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return 0;
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}
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