标签：des style blog http color os io strong
解题报告
题意：
又是求面积并
思路：
又是求面积并，还被坑了，题目明明描述的是int坐标，用了double才过。。。
#include <algorithm>
#include <iostream>
#include <cstring>
#include <cstdio>
using namespace std;
struct Seg {
double lx,rx,h;
int v;
friend bool operator <(Seg a,Seg b) {
return a.h<b.h;
}
} seg[2100];
double _hash[4100],sum[201000];
int lz[201000];
void push_up(int rt,int l,int r) {
if(lz[rt])sum[rt]=_hash[r+1]-_hash[l];
else if(l==r)sum[rt]=0;
else sum[rt]=sum[rt<<1]+sum[rt<<1|1];
}
void update(int rt,int l,int r,int ql,int qr,int v) {
if(ql>r||qr<l)return ;
if(ql<=l&&r<=qr) {
lz[rt]+=v;
push_up(rt,l,r);
return ;
}
int mid=(l+r)>>1;
update(rt<<1,l,mid,ql,qr,v);
update(rt<<1|1,mid+1,r,ql,qr,v);
push_up(rt,l,r);
}
int main() {
int t,n,i,j;
double x1,x2,y1,y2;
scanf("%d",&t);
while(t--) {
memset(sum,0,sizeof(sum));
memset(_hash,0,sizeof(_hash));
memset(lz,0,sizeof(lz));
scanf("%d",&n);
for(i=0; i<n; i++) {
scanf("%lf%lf%lf%lf",&x1,&y1,&x2,&y2);
_hash[i]=x1,_hash[i+n]=x2;
seg[i].lx=x1,seg[i].rx=x2,seg[i].v=1,seg[i].h=y1;
seg[i+n].lx=x1,seg[i+n].rx=x2,seg[i+n].v=-1,seg[i+n].h=y2;
}
sort(_hash,_hash+n*2);
sort(seg,seg+n*2);
int m=unique(_hash,_hash+n*2)-_hash;
double ans=0;
for(i=0; i<n*2-1; i++) {
int ql=lower_bound(_hash,_hash+m,seg[i].lx)-_hash;
int qr=lower_bound(_hash,_hash+m,seg[i].rx)-_hash-1;
update(1,0,m-1,ql,qr,seg[i].v);
ans+=sum[1]*(seg[i+1].h-seg[i].h);
}
printf("%.0lf\n",ans);
}
return 0;
}
| Area Coverage |
| Time Limit: 10000ms, Special Time Limit:2500ms, Memory Limit:65536KB |
| Total submit users: 22, Accepted users: 16 |
| Problem 12884 : No special judgement |
| Problem description |
|
In this day and age, a lot of the spying on other countries is done with the use of satellites and drones equipped with cameras. All these photographs of various sizes and from various sources can be combined to give a picture of the country as a whole. |
| Input |
|
On the first line one positive number: the number of test cases, at most 100. After that per test case: |
| Output |
|
Per test case: |
| Sample Input |
2 3 0 6 20 16 14 0 24 10 50 50 60 60 2 0 0 20 10 10 4 14 8 |
| Sample Output |
376 200 |
| Problem Source |
| BAPC preliminary 2013 |
HNU12884_Area Coverage(扫描线/线段树+离散化),布布扣,bubuko.com
HNU12884_Area Coverage(扫描线/线段树+离散化)
标签：des style blog http color os io strong
原文地址：http://blog.csdn.net/juncoder/article/details/38637953
