A very hard mathematic problem Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://acm.hdu.edu.cn/showproblem.php?pid=4282 Description Haoren is very good at solving mathematic problems. Today he is working a problem like this: Find three positive in…

题意:问方程X^Z + Y^Z + XYZ = K (X<Y,Z>1)有多少个正整数解 (K<2^31) 解法:看K不大,而且不难看出 Z<=30, X<=sqrt(K), 可以枚举X和Z,然后二分找Y,这样的话不把pow函数用数组存起来的话好像会T,可以先预处理出1~47000的2~30次幂,这样就不会T了. 但是还可以简化,当Z=2时,X^2+Y^2+2XY = (X+Y)^2 = K, 可以特判下Z= 2的情况,即判断K是否为平方数,然后Z就可以从3开始了,这样的话X^…

由于k的范围是0-2^31,而且x,y,z都是正整数,由题易知道2<=z<31,1<=x<y;所以直接枚举就好了!!! #include<iostream> #include<stdio.h> #include<algorithm> #include<iomanip> #include<cmath> #include<stdlib.h> #include<cstring> #include<v…

pid=4972" target="_blank" style="">题目链接:hdu 4972 A simple dynamic programming problem 题目大意:两支球队进行篮球比赛,每进一次球后更新比分牌,比分牌的计数方法是记录两队比分差的绝对值,每次进球的分可能是1,2,3分. 给定比赛中的计分情况.问说最后比分有多少种情况. 解题思路:分类讨论: 相邻计分为1-2或者2-1的时候,会相应有两种的的分情况 相邻计分之差大于3或…

A Very Simple Problem Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 1022    Accepted Submission(s): 500 Problem Description This is a very simple problem. Given three integers N, x, and M, you…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4975 Problem Description Dragon is studying math. One day, he drew a table with several rows and columns, randomly wrote numbers on each elements of the table. Then he counted the sum of each row and col…

http://acm.hdu.edu.cn/showproblem.php?pid=4282 对于方程X^Z + Y^Z + XYZ = K,已知K求此方程解的个数,其中要求X<Y,Z>1,而K的范围是0到2^31. 首先我们来分析Z的范围:由于X,Y为正整数,X < Y,则1 < X < Y, =====> Y >= 2 => X^Z + Y^Z + XYZ > Y^Z => 2^Z <= Y^Z < 2^31 所以得到2 <…

任意门:http://acm.hdu.edu.cn/showproblem.php?pid=6319 Problem A. Ascending Rating Time Limit: 10000/5000 MS (Java/Others)    Memory Limit: 524288/524288 K (Java/Others)Total Submission(s): 5943    Accepted Submission(s): 2004 Problem Description Before…

A simple Gaussian elimination problem. Time Limit: 1000ms Memory Limit: 65536KB This problem will be judged on HDU. Original ID: 497564-bit integer IO format: %I64d      Java class name: Main Dragon is studying math. One day, he drew a table with sev…

A simple brute force problem. Time Limit: 1000ms Memory Limit: 65536KB This problem will be judged on HDU. Original ID: 497164-bit integer IO format: %I64d      Java class name: Main There's a company with several projects to be done. Finish a projec…