Error Curves Josephina is a clever girl and addicted to Machine Learning recently. She pays much attention to a method called Linear Discriminant Analysis, which has many interesting properties.In order to test…

UVA 1476 1476 - Error Curves 题目链接 题意:给几条下凹二次函数曲线.然后问[0,1000]全部位置中,每一个位置的值为曲线中最大值的值,问全部位置的最小值是多少 思路:三分法,因为都是下凹函数,所以全部曲线合并起来.仍然是一个下凹函数.满足单峰.用三分求极值 代码: #include <cstdio> #include <cstring> #include <cmath> #include <algorithm> using n…

Josephina is a clever girl and addicted to Machine Learning recently. She pays much attention to a method called Linear Discriminant Analysis, which has many interesting properties. In order to test the algorithm's efficiency, she collects many datas…

对x的坐标三分: #include<cstdio> #include<algorithm> #define maxn 10009 using namespace std; double a[maxn],b[maxn],c[maxn]; int n; double f(double x) { double ans=-999999999.0,t; ;i<n;i++) { t=a[i]*x*x+b[i]*x+c[i]; ans=max(ans,t); } return ans; }…

Problem Description Josephina is a clever girl and addicted to Machine Learning recently. She pays much attention to a method called Linear Discriminant Analysis, which has many interesting properties. In order to test the algorithm's efficiency, she…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=3714 懂了三分思想和F(x)函数的单调性质,这题也就是水题了 #include "stdio.h" //最后得到的F(x)函数要么是单调的,要么是先减后增的,有了这个性质,就可以三分了~ #include "string.h" #define N 10005 #define eps 1e-9 #define INF 0x3fffffff struct node { in…

http://acm.hdu.edu.cn/showproblem.php?pid=3714 [题意]: 题目意思看了很久很久,简单地说就是给你n个二次函数,定义域为[0,1000], 求x在定义域中每个x所在的n个函数的最大值的最小值.很拗口吧,显然这题不是组队或者耐心的做是不知道性质的,至少我没看出来.网上说是三分,我画了几个图,确实是.根据二次函数的性质,增长的快慢已经确定了,那的确是单峰的.那就OK了.另外eps的问题1e-8还是wa,1e-9AC.想了下,因为有系数a,b,c的缘故,一…

//#pragma comment(linker, "/STACK:1024000000,1024000000") #include<cstdio> #include<cstring> #include<cstdlib> #include<algorithm> #include<iostream> #include<sstream> #include<cmath> #include<climits…

Error Curves Time Limit:3000MS    Memory Limit:0KB    64bit IO Format:%lld & %llu SubmitStatusPracticeUVALive 5009 Appoint description: Description Josephina is a clever girl and addicted to Machine Learning recently. She pays much attention to a met…

Error Curves Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 1198    Accepted Submission(s): 460 Problem Description Josephina is a clever girl and addicted to Machine Learning recently. She pa…