#include <iostream>
#include <algorithm>
#include <cstdlib>
#include <cstdio>
#include <cstring>
#include <map>
#define Mid(x) ((tree[(x)].l+tree[(x)].r)/2)
#define Left(x) ((x)<<1)
#define Right(x) ((x)<<1|1)
#define Lson(x) Left(x),tree[(x)].l,Mid(x)
#define Rson(x) Right(x),Mid(x)+1,tree[(x)].r
using namespace std;
const int maxn=10010;
struct SegTree
{
    int l,r,key;
} tree[maxn<<3];
struct Poster
{
    int l,r;
} poster[maxn];
int n,a[maxn<<1],hash[maxn];
map<int,int>pos;
void Build(int root,int l,int r)
{
    tree[root].l=l,tree[root].r=r,tree[root].key=0;
    if (l==r)return;
    Build(Lson(root));
    Build(Rson(root));
}
void Update(int root,int l,int r,int key)
{
    if (tree[root].l==l&&tree[root].r==r)
    {
        tree[root].key=key;
        return;
    }
    if (tree[root].key)
    {
        Update(Lson(root),tree[root].key);
        Update(Rson(root),tree[root].key);
        tree[root].key=0;
    }
    if (r<=Mid(root))Update(Left(root),l,r,key);
    else if (l>Mid(root))Update(Right(root),l,r,key);
    else Update(Left(root),l,Mid(root),key),Update(Right(root),Mid(root)+1,r,key);
    return;
}
int Query(int root)
{
    if (tree[root].key)
    {
        hash[tree[root].key]++;
        return hash[tree[root].key]==1;
    }
    if (tree[root].l==tree[root].r)return 0;
    return Query(Left(root))+Query(Right(root));
}
int main()
{
  //  freopen("input.in","r",stdin);
   // freopen("output.out","w",stdout);
    int total,i,tot;
    scanf("%d",&total);
    while (total--)
    {
        scanf("%d",&n);
        for (i=0;i<n;i++)
        {
            scanf("%d%d",&poster[i].l,&poster[i].r);
            a[i*2]=poster[i].l;
            a[i*2+1]=poster[i].r;
        }
        sort(a,a+2*n);
        tot=0;
        pos.clear();
        for (i=0;i<2*n;i++)
        {
            if (i>0&&a[i]==a[i-1])continue;
            if (i>0&&abs(a[i]-a[i-1])>1)tot++;
            pos[a[i]]=++tot;
        }
        Build(1,1,tot);
        for (i=0;i<n;i++)Update(1,pos[poster[i].l],pos[poster[i].r],i+1);
        memset(hash,0,sizeof(hash));
        printf("%d\n",Query(1));
    }
}

PS：论坛中各种小数据都过，已经 离散化+点化了，不知哪里出现re问题。

• 线段树开大点, 因为点是两倍, 线段树至少得开 maxN * 6 (2417) stupidjohn 2011-08-04 20:14:22
  • Re:线段树开大点, 因为点是两倍, 线段树至少得开 maxN * 6 (0) B10330224 2011-12-25 07:35:46