Dreisam Equations { 两个网站的题有点不一样(ZJH有特判)POJ时间卡得紧,建议去POJ过 } 题目大意: 给你一个字符串:是一个等式,等式左边是一个数,右边由若干个数和()构成,要求加入(+.- 或 *)来使得等式成立,注意:这道题抛弃了原本的优先级,除了括号一律采用从左到右的计算顺序. 题目陷阱: 测试数据中可能有 2= (1)(1) 或者 2=((1)1) ,不一定只是在空格处加符号. 题目思路: 可以对原字符串进行加工,也就是先预先处理空格,不过这样子比较麻烦,可以考…

原题地址:http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=145 题目大意:在给定的等式右边数字之间加上加.减.乘运算符,使等式成立. 解题思路:遍历每一种情况,有计算式子的结果,若等于左边的数字,则输出答案. 题目输入的几点: 所给的式子左边是一个数字,然后是一个等号,之间可能有空格,也可能没有.然后右边的式子每两个数字之间至少有一个空格或者括号,以便区分,因此,两个数字之间可能没有空格只有括号.所以先处理右边的式子的字符串…

H - Sorting Slides 应该是个二分匹配的模板题的,但我还不会写 = = 其实数据规模很小,就用贪心的方法就水过了(没加vis判冲突wa了几发,从此开始艰难的没有1A 的生活) #include <stdio.h> #include <cstring> #include <cstdlib> #include <algorithm> #include <cmath> using namespace std; #define lson…

Special equations Time Limit:1000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 4569 Description Let f(x) = a nx n +...+ a 1x +a 0, in which a i (0 <= i <= n) are all known integers. We call f(x) 0 (mod…

“矩阵代数初步”(Introduction to MATRIX ALGEBRA)课程由Prof. A.K.Kaw(University of South Florida)设计并讲授. PDF格式学习笔记下载(Academia.edu) 第5章课程讲义下载(PDF) Summary Consistent and inconsistent system A system of equations $$[A][X]=[B]$$ where $[A]$ is called the coefficient…

1.Introduction 2.First-order Differential Equations Exercise2.1. Find solutons of the following intial-value problems in $\bbR^2$: (1)$2u_y-u_x+xu=0$ with $u(x,0)=2xe^{x^2/2}$; (2)$u_y+(1+x^2)u_x-u=0$ with $u(x,0)=\arctan x$. Solution: (1)Since $(-1,…

Introduce The article shows a way to use math equations to represent code's logical. Key ideas logical first Get readers to see the logical first, so prefer to keep a 'where' section to describe variables separately. Pure function conception I am thi…

All the two important problems that the EM theory trys to describe and explain are propogation and radiation of EM wave, on the basic of Maxwell Equations. So we have to talk about the Maxwell Equations firstly  ,the greatest achievement in my opinio…

FITTING A MODEL VIA CLOSED-FORM EQUATIONS VS. GRADIENT DESCENT VS STOCHASTIC GRADIENT DESCENT VS MINI-BATCH LEARNING. WHAT IS THE DIFFERENCE? In order to explain the differences between alternative approaches to estimating the parameters of a model,…

Description Consider equations having the following form: a*x1^2+b*x2^2+c*x3^2+d*x4^2=0 a, b, c, d are integers from the interval [-50,50] and any of them cannot be 0. It is consider a solution a system ( x1,x2,x3,x4 ) that verifies the equation, xi…