Intersection Time Limit: 4000/4000 MS (Java/Others)    Memory Limit: 512000/512000 K (Java/Others) Problem Description Matt is a big fan of logo design. Recently he falls in love with logo made up by rings. The following figures are some famous examp…

题意:给定两个圆环,求两个圆环的面积交. 析:很容易知道,圆环面积交就是,大圆与大圆面积交 - 大圆和小圆面积交 - 小圆和大圆面积交 + 小圆和小圆面积交. 代码如下: #pragma comment(linker, "/STACK:1024000000,1024000000") #include <cstdio> #include <string> #include <cstdlib> #include <cmath> #includ…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5120 A ring is a 2-D figure bounded by two circles sharing the common center. The radius for these circles are denoted by r and R (r < R). For more details, refer to the gray part in the illustration bel…

pro:飞行员去轰炸一个小岛,给出炸弹落地点的位置信息,以及轰炸半径:按顺时针或者逆时针给出小岛的边界点. 求被轰炸的小岛面积. sol:即是求圆和多边形的面积交. (只会套板子的我改头换面,先理解然后手打一遍. 首先,我们还是用三角剖分多边形,求“有向面积”,有向面积可以避免凹多边形存在的情况,或者二者相离的情况. 我们把圆心设为起点,然后对于一个三角形,求它和圆的面积交. 此时有4中情况. 1,三角形在圆的内部.    即OA ,OB的出度都不大于r. 2,一个点在圆外,一个点在圆内. 那么…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5120 解题报告:给你两个完全相同的圆环,要你求这两个圆环相交的部分面积是多少? 题意看了好久没懂.圆环由一个大圆里面套一个小圆,中间部分就是圆环,两圆环相交面积 = 大圆相交的面积 - 2*大圆与小圆相交的面积 + 小圆与小圆相交的面积. 也就是说,这题就可以化为求两个圆的相交的面积了.可以利用两个圆的方程,求出圆的交点所在的直线,然后求出圆心到这条直线的距离,就可以求出两个圆对应的扇形的圆心角是多…

题意:给定两个圆环,求两个圆环相交的面积. 思路:由于圆心和半径不一样,分了好多种情况,后来发现只要把两个圆相交的函数写好之后就不需要那么复杂了.两个圆相交的面积的模板如下: double area_of_overlap(point c1, double r1, point c2, double r2) { double d = dist(c1, c2); ) ; ) { double r = min(r1, r2); return PI * r * r; } double x = (d * d…

题意:给出多边形的顶点坐标.圆的圆心坐标和半径,求面积交 sol:又是模板题啦= = 注意poj的C++好像认不出hypot函数,要稍微改写一下. hypot(double x,double y):即返回sqrt(x*x+y*y)的值 #include<vector> #include<list> #include<map> #include<set> #include<deque> #include<queue> #include&…

题意:告诉你两个圆环,求圆环相交的面积. /* gyt Live up to every day */ #include<cstdio> #include<cmath> #include<iostream> #include<algorithm> #include<vector> #include<stack> #include<cstring> #include<queue> #include<set&…

Intersection Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=5120 Description Matt is a big fan of logo design. Recently he falls in love with logo made up by rings. The following figures are some famous examples…

Problem Description Matt is a big fan of logo design. Recently he falls in love with logo made up by rings. The following figures are some famous examples you may know. A ring is a 2-D figure bounded by two circles sharing the common center. The radi…