洛谷P2894 [USACO08FEB]酒店Hotel_區間更新_區間查詢
阿新 • • 發佈:2018-12-11
Code:
#include<cstdio>
#include<algorithm>
#include<cstring>
using namespace std;
const int N = 200000+5;
int n,m,k;
struct Segment_Tree{
int lazy,left,right,maxv;
}Seg[N<<2];
inline void push_down(int o,int l,int r)
{
if(Seg[o].lazy == -1 || l==r)return;
int mid = (l+ r)>>1;
int lz = Seg[o].lazy, ls=o<<1, rs=(o<<1)|1;
Seg[ls].lazy = Seg[rs].lazy = lz;
Seg[ls].maxv = lz==0 ? mid-l+1: 0;
Seg[rs].maxv = lz==0 ? r-mid: 0;
Seg[ ls].left = Seg[ls].right = Seg[ls].maxv;
Seg[rs].left = Seg[rs].right = Seg[rs].maxv;
Seg[o].lazy = -1;
}
inline void update_seg(int o,int l,int r)
{
int mid = (l+r)>>1, ls=o<<1, rs=(o<<1)|1 ;
Seg[o].maxv = max(Seg[ls].maxv, Seg[rs].maxv);
Seg[o].maxv = max(Seg[o].maxv, Seg[ls].right+Seg[rs].left);
Seg[o].left = Seg[ls].maxv == mid-l+1 ? Seg[ls].maxv+Seg[rs].left : Seg[ls].left;
Seg[o].right = Seg[rs].maxv == r-mid ? Seg[rs].maxv+Seg[ls].right: Seg[rs].right;
}
void build_Tree(int l,int r,int o){
if(l>r)return;
if(l==r)
{
Seg[o].left = Seg[o].right = Seg[o].maxv = 1;
Seg[o].lazy = -1;
return;
}
int mid = (l+r)>>1, ls=o<<1, rs=(o<<1)|1;
build_Tree(l,mid,ls);
build_Tree(mid+1,r,rs);
update_seg(o,l,r);
Seg[o].lazy = -1;
}
void update(int L,int R,int l,int r,int val,int o){
if(L>R)return;
if(L>=l&&R<=r)
{
Seg[o].lazy = val;
Seg[o].maxv = (val==0)?R-L+1: 0;
Seg[o].left = Seg[o].right = Seg[o].maxv;
return;
}
push_down(o,L,R);
int mid = (L+R)>>1,ls=o<<1, rs=(o<<1)|1;
if(l<=mid) update(L,mid,l,r,val,ls);
if(r>mid) update(mid+1,R,l,r,val,rs);
update_seg(o,L,R);
}
int query(int o,int l,int r){
int mid=(l+r)>>1, ls=o<<1, rs=(o<<1)|1, ans;
push_down(o,l,r);
if(Seg[o].left >= k)
ans = l;
else if(Seg[ls].maxv >=k )
ans = query(ls,l,mid);
else if(Seg[ls].right+Seg[rs].left >= k)
ans = mid+1-Seg[ls].right;
else
ans = query( rs ,mid+1,r);
update_seg(o,l,r);
return ans;
}
inline int solve_1(){
if(Seg[1].maxv < k)return 0;
return query(1,1,n);
}
int main()
{
// freopen("in.txt","r",stdin);
// freopen("out.txt","w",stdout);
scanf("%d%d",&n,&m);
build_Tree(1,n,1);
while(m--)
{
int op,x,y;
scanf("%d%d",&op,&x);
if(op==1)
{
k=x;
int ans=solve_1();
printf("%d\n",ans);
if(ans!=0)update(1,n,ans,ans+k-1,1,1);
}
if(op==2)
{
scanf("%d",&y);
update(1,n,x,x+y-1,0,1);
}
}
return 0;
}