OJ-Problems-Source/POJ/3667.cpp
2016-08-16 12:43:54 +08:00

162 lines
4.4 KiB
C++

/// General includes
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
using namespace std;
/// 区间赋值更新, 区间合并, 查找左端
namespace AttributeSumSegmentTree
{
const int MAXN = 100100;
const int MAXTREENODE = MAXN << 3;
const int ATTR_BY_DEFAULT=-1;///默认初始化属性 -1 无需操作 0 子树有住户离开 1 子树有住户进入
struct node
{
int lt,rt;
int lsum,rsum,sum;
int attr;
};
node tree[MAXTREENODE];
void build(int L,int R,int _indexer=1)
{
tree[_indexer].lt=L;
tree[_indexer].rt=R;
tree[_indexer].attr=ATTR_BY_DEFAULT;
tree[_indexer].lsum=tree[_indexer].rsum=tree[_indexer].sum=R-L+1;
if(L!=R)
{
int mid=(L+R)>>1;
build(L,mid,_indexer<<1);
build(mid+1,R,_indexer<<1|1);
}
}
void update(int L,int R,int NewAttr,int _indexer=1)
{
if(L==tree[_indexer].lt&&R==tree[_indexer].rt)
{
tree[_indexer].lsum=tree[_indexer].rsum=tree[_indexer].sum=
NewAttr==1 ? 0 : tree[_indexer].rt-tree[_indexer].lt+1 ; /// Same as R-L+1
tree[_indexer].attr=NewAttr;
return;
}
/// Push Down (updated)
if(tree[_indexer].attr!=-1)
{
/// Sync the Attribute to sub-tree
tree[_indexer<<1].attr=tree[_indexer<<1|1].attr=tree[_indexer].attr;
tree[_indexer].attr=-1;
tree[_indexer<<1].rsum=tree[_indexer<<1].lsum=tree[_indexer<<1].sum= tree[_indexer<<1].attr==1 ? 0 : tree[_indexer<<1].rt-tree[_indexer<<1].lt+1;
tree[_indexer<<1|1].rsum=tree[_indexer<<1|1].lsum=tree[_indexer<<1|1].sum= tree[_indexer<<1|1].attr==1 ? 0 : tree[_indexer<<1|1].rt-tree[_indexer<<1|1].lt+1;
}
int mid=(tree[_indexer].lt+tree[_indexer].rt)>>1;
if(R<=mid)
{
update(L,R,NewAttr,_indexer<<1);
}
else if(L>mid)
{
update(L,R,NewAttr,_indexer<<1|1);
}
else
{
update(L,mid,NewAttr,_indexer<<1);
update(mid+1,R,NewAttr,_indexer<<1|1);
}
/// Push Up (updated)
tree[_indexer].lsum=tree[_indexer<<1].lsum; /// left & left
tree[_indexer].rsum=tree[_indexer<<1|1].rsum; /// right & right
if(tree[_indexer<<1].lsum == tree[_indexer<<1].rt-tree[_indexer].lt+1)
{
/// Father.LeftSum == RightSon.LeftSum + LeftSon.LeftSum
tree[_indexer].lsum+=tree[_indexer<<1|1].lsum;
}
/// Why tree[_indexer].rsum but not tree[_indexer<<1|1].rsum ???
if(tree[_indexer].rsum==tree[_indexer<<1|1].rt-tree[_indexer<<1|1].lt+1)
{
/// Father.RightSum == LeftSon.RightSum + RightSon.RightSum
tree[_indexer].rsum+=tree[_indexer<<1].rsum;
}
tree[_indexer].sum=max(max(tree[_indexer<<1].sum,tree[_indexer<<1|1].sum),tree[_indexer<<1].rsum+tree[_indexer<<1|1].lsum);
}
int query(int Val,int _indexer=1)
{
if(tree[_indexer].lt==tree[_indexer].rt)
{
return tree[_indexer].lt;
}
/// Push Down (updated)
if(tree[_indexer].attr!=-1)
{
/// Sync the Attribute to sub-tree
tree[_indexer<<1].attr=tree[_indexer<<1|1].attr=tree[_indexer].attr;
tree[_indexer].attr=-1;
tree[_indexer<<1].rsum=tree[_indexer<<1].lsum=tree[_indexer<<1].sum= tree[_indexer<<1].attr==1 ? 0 : tree[_indexer<<1].rt-tree[_indexer<<1].lt+1;
tree[_indexer<<1|1].rsum=tree[_indexer<<1|1].lsum=tree[_indexer<<1|1].sum= tree[_indexer<<1|1].attr==1 ? 0 : tree[_indexer<<1|1].rt-tree[_indexer<<1|1].lt+1;
}
int Mid=(tree[_indexer].rt+tree[_indexer].lt)>>1;
/// Left
if(tree[_indexer<<1].sum>=Val)
{
return query(Val,_indexer<<1);
}
/// Both Left and Right
else if(tree[_indexer<<1].rsum+tree[_indexer<<1|1].lsum >= Val)
{
return Mid-tree[_indexer<<1].rsum+1;
}
else /// Right
{
return query(Val,_indexer<<1|1);
}
}
}/// End of namespace AttributeSumSegmentTree
int main()
{
using namespace AttributeSumSegmentTree;
int N,M;
scanf("%d %d",&N,&M);
build(1,N);
while(M--)
{
int op;
scanf("%d",&op);
if(op==1) /// Check in
{
int x;
scanf("%d",&x);
if(tree[1].sum<x)
{
printf("0\n");continue;
}
int ans=query(x);
printf("%d\n",ans);
update(ans,ans+x-1,1);
}
else /// Check out
{
int a,b;
scanf("%d %d",&a,&b);
update(a,a+b-1,0);
}
}
return 0;
}