题意 PDF 分析 两两圆求交点,对每个圆弧按半径抖动. 时间复杂度\(O(T n^2)\) 代码 #include<iostream> #include<cstdio> #include<cstdlib> #include<cmath> #include<set> #include<map> #include<queue> #include<stack> #include<algorithm> #…

转载请注明出处: http://www.cnblogs.com/fraud/          ——by fraud Viva Confetti Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 881   Accepted: 361 Description Do you know confetti? They are small discs of colored paper, and people throw them a…

Viva Confetti Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 1025   Accepted: 422 Description Do you know confetti? They are small discs of colored paper, and people throw them around during parties or festivals. Since people throw lots…

计算几何:按顺序给n个圆覆盖.问最后能够有几个圆被看见.. . 对每一个圆求和其它圆的交点,每两个交点之间就是可能被看到的圆弧,取圆弧的中点,往外扩展一点或者往里缩一点,从上往下推断有没有圆能够盖住这个点,能盖住这个点的最上面的圆一定是可见的 Viva Confetti Time Limit: 2 Seconds      Memory Limit: 65536 KB Do you know confetti? They are small discs of colored paper, and…

思路: 小圆面是由小圆弧围成.那么找出每条小圆弧,如果小圆弧,在小圆弧中点上下左右进行微小位移的所得的点一定在一个小圆面内. 找到最后覆盖这个小点的圆一定是可见的. 圆上的点按照相邻依次排序的关键量为极角(0,2PI) 用中心点代替圆弧本身是否被圆覆盖 #include<cstdio> #include<cmath> #include<cstring> #include<algorithm> #include<iostream> #include…

这个题目的方法是将圆盘分成一个个圆环,然后判断这些圆环是否被上面的圆覆盖: 如果这个圆的圆周上的圆弧都被上面的覆盖,暂时把它标记为不可见: 然后如果他的头上有个圆,他有个圆弧可见,那么他自己本身可见,并且可以把这条圆弧下面的第一个圆重新标记为可见: 另外,圆弧可见还是不可见利用它的中点来进行判断: #include <cstdio> #include <cmath> #include <cstring> #include <algorithm> #inclu…

一次放下n个圆 问最终可见的圆的数量 应该是比较经典的问题吧 考虑一个圆与其他每个圆的交点O(n)个 将其割成了O(n)条弧 那么看每条弧的中点 分别向内向外调动eps这个点 则最上面的覆盖这个点的圆可见O(n) 总时间复杂度O(n ** 3) 怕炸精度,代码基本抄的rjl的 #include<cstdio> #include<cstring> #include<cstdlib> #include<algorithm> #include<iostrea…

比赛链接: http://vjudge.net/contest/view.action?cid=48069#overview 题目来源: lrj训练指南---二维几何计算   ID Title Problem A Morley's Theorem   (向量夹角+向量旋转+两直线交点) Problem B That Nice Euler Circuit  (欧拉定理 F = E + 2 - V, 求直线相交+ 判断点是否在直线上)   Problem C Dog Distance   (好题,…

Viva Confetti Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 761   Accepted: 319 Description Do you know confetti? They are small discs of colored paper, and people throw them around during parties or festivals. Since people throw lots…

This list gives you suggestions helpful in preparing to defend your thesis: I know my thesis thoroughly    I have written a one-page summary of each chapter    I have continued to work with my thesis after submission or have begun to prepare a confer…