poj-1151-Atlantis-线段树求面积并

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很裸的线段树求面积并。
坐标需要离散化一下。
#include<stdio.h>#include<iostream>#include<stdlib.h>#include<string.h>#include<algorithm>#include<vector>#include<math.h>#include<map>#pragma comment(linker, "/STACK:1024000000,1024000000")using namespace std;#define maxn 11000#define mem(a,b) (memset(a),b,sizeof(a))#define lmin 1#define rmax len#define lson l,(l+r)/2,rt<<1#define rson (l+r)/2+1,r,rt<<1|1#define root lmin,rmax,1#define now l,r,rt#define int_now int l,int r,int rt#define INF 99999999#define LL long long#define mod 10007#define eps 1e-6#define zero(x) (fabs(x)<eps?0:x)map<double,int>mp;double du[4010];int len;struct list{    double x1,y1;    double x2,y2;}node[maxn];struct linen{    double y1,y2;    int leap;    double x;    friend bool operator <(const linen &a,const linen &b)    {        if(zero(a.x-b.x)!=0) return a.x<b.x;        else return a.leap>b.leap;    }}line[maxn*2];double num[maxn*4*4*2];int cover[maxn*4*4*2];void push_up(int_now){    if(cover[rt]==0)    {        num[rt]=num[rt<<1]+num[rt<<1|1];    }    if(cover[rt]>=1)    {        num[rt]=du[r+1]-du[l];    }  //  cout<<rt<<" "<<du[l]<<"===="<<du[r+1]<<" "<<cover[rt]<<" "<<num[rt]<<" "<<sum[rt]<<endl;}void push_down(int_now){}void creat(int_now){    memset(cover,0,sizeof(cover));    memset(num,0,sizeof(num));}void updata(int ll,int rr,int x,int_now){    if(ll>r||rr<l)return;    if(ll<=l&&rr>=r)    {       // cout<<l<<" "<<r<<"-"<<du[l]<<" "<<du[r+1]<<" "<<endl;        cover[rt]+=x;        push_up(now);        return;    }    updata(ll,rr,x,lson);    updata(ll,rr,x,rson);    push_up(now);}int main(){    int t,n,s;    int cas=0;    while(~scanf("%d",&n)&&n)    {        cas++;        s=0;        for(int i=1;i<=n;i++)        {            scanf("%lf%lf%lf%lf",&node[i].x1,&node[i].y1,&node[i].x2,&node[i].y2);            du[++s]=node[i].x1;            du[++s]=node[i].y1;            du[++s]=node[i].x2;            du[++s]=node[i].y2;            line[i*2-1].x=node[i].x1;            line[i*2-1].y1=node[i].y1;            line[i*2-1].y2=node[i].y2;            line[i*2-1].leap=1;            line[i*2].x=node[i].x2;            line[i*2].y1=node[i].y1;            line[i*2].y2=node[i].y2;            line[i*2].leap=-1;        }        sort(line+1,line+n*2+1);        sort(du+1,du+s+1);        du[0]=-1;        len =0;        mp.clear();        for(int i=1;i<=s;i++)        {            if(du[i]!=du[i-1])            {                mp[du[i]]=++len;                du[len]=du[i];            }        }        creat(root);        double st=0;        double are=0.0;        for(int i=1;i<=len;i++)        {           // cout<<i<<"----"<<du[i]<<endl;        }        len--;       // cout<<1<<" "<<len<<" "<<1<<" "<<endl;        for(int i=1;i<=n*2;i++)        {            int l,r;            l=mp[line[i].y1];            r=mp[line[i].y2];            if(zero(line[i].x-st)!=0)            {                are+=(line[i].x-st)*num[1];                st=line[i].x;            }           // cout<<line[i].x<<" "<<line[i].y1<<" "<<line[i].y2<<" "<<" "<<line[i].leap<<endl;            updata(l,r-1,line[i].leap,root);            //cout<<l<<" "<<r<<" "<<are<<endl;        }        printf("Test case #%d\n",cas);        printf("Total explored area: %.2f\n\n",are);    }    return 0;}
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