bzoj1176: [Balkan2007]Mokia

http://www.lydsy.com/JudgeOnline/problem.php?id=1176

CDQ分治

#include<cstdio>
#include<iostream>
#include<algorithm>

#define lowbit(x) x&-x 

using namespace std;

#define N 160001
#define M 10001

typedef long long LL;

int w;
LL c[2000001];

struct node
{
    int id;
    int x,y,bl,mul;
    bool ty;
}e[N+M*4],tmp[N+M*4];

LL ans[M];

void read(int &x)
{
    x=0; int f=1; char c=getchar();
    while(!isdigit(c)) { if(c=='-') f=-1; c=getchar(); }
    while(isdigit(c)) { x=x*10+c-'0'; c=getchar(); }
    x*=f;
}

bool cmp(node p,node q)
{
    if(p.x!=q.x) return p.x<q.x;
    return p.ty<q.ty;
}

void change(int x,int k)
{
    while(x<=w)
    {
        c[x]+=k;
        x+=lowbit(x);
    }
}

LL query(int x)
{
    LL sum=0;
    while(x)
    {
        sum+=c[x];
        x-=lowbit(x);
    }
    return sum;
}

void solve(int l,int r)
{
    if(l==r) return;
    int mid=l+r>>1;
    int sum=0;
    for(int i=l;i<=r;++i)
    {
        if(!e[i].ty && e[i].id<=mid) change(e[i].y,e[i].mul);
        else if(e[i].ty && e[i].id>mid) ans[e[i].bl]+=e[i].mul*query(e[i].y); 
    }
    for(int i=l;i<=r;++i)
    {
        if(!e[i].ty && e[i].id<=mid) change(e[i].y,-e[i].mul);
    }
    int L=l,R=mid+1;
    for(int i=l;i<=r;++i)
    {
        if(e[i].id<=mid) tmp[L++]=e[i];
        else tmp[R++]=e[i];
    }
    for(int i=l;i<=r;++i) e[i]=tmp[i];
    solve(l,mid);
    solve(mid+1,r);
}

int main()
{
    int s;
    read(s); read(w);
    int ty,lx,ly,rx,ry,k;
    int tot=0,cnt=0;
    while(scanf("%d",&ty))
    {
        if(ty==1)
        {
            e[++tot].id=tot;
            read(e[tot].x); 
            read(e[tot].y);
            read(e[tot].mul);
        }
        else if(ty==2)
        {
            read(lx); read(ly); read(rx); read(ry);
            cnt++;
            e[++tot].id=tot; e[tot].bl=cnt; e[tot].mul=1; e[tot].ty=true; e[tot].x=rx; e[tot].y=ry;
            e[++tot].id=tot; e[tot].bl=cnt; e[tot].mul=1; e[tot].ty=true; e[tot].x=lx-1; e[tot].y=ly-1;
            e[++tot].id=tot; e[tot].bl=cnt; e[tot].mul=-1; e[tot].ty=true; e[tot].x=lx-1; e[tot].y=ry;
            e[++tot].id=tot; e[tot].bl=cnt; e[tot].mul=-1; e[tot].ty=true; e[tot].x=rx; e[tot].y=ly-1;
            
        }
        else break;
    }
    sort(e+1,e+tot+1,cmp);
    solve(1,tot);
    for(int i=1;i<=cnt;++i) cout<<ans[i]<<'
';
}
原文地址:https://www.cnblogs.com/TheRoadToTheGold/p/8057698.html