题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=1562 Problem Description Happy new year to everybody!Now, I want you to guess a minimum number x betwwn 1000 and 9999 to let (1) x % a = 0;(2) (x+1) % b = 0;(3) (x+2) % c = 0;and a, b, c are integers be…

Problem Description Happy new year to everybody! Now, I want you to guess a minimum number x betwwn 1000 and 9999 to let (1) x % a = 0; (2) (x+1) % b = 0; (3) (x+2) % c = 0; and a, b, c are integers between 1 and 100. Given a,b,c, tell me what is the…

HDU.1394 Minimum Inversion Number (线段树 单点更新 区间求和 逆序对) 题意分析 给出n个数的序列,a1,a2,a3--an,ai∈[0,n-1],求环序列中逆序对最少的个数. 前置技能 环序列 还 线段树的逆序对求法 逆序对:ai > aj 且 i < j ,换句话说数字大的反而排到前面(相对后面的小数字而言) 环序列:把第一个放到最后一个数后面,就是一次成环,一个含有n个元素序列有n个环序列. 线段树的逆序对求法:每个叶子节点保存的是当前值数字的个数.根…

hdu 6216 A Cubic number and A Cubic Number[数学] 题意:判断一个素数是否是两个立方数之差,就是验差分.. 题解:只有相邻两立方数之差才可能,,因为x^3-y^3=(x-y)(x^2+xy+y^2),看(x-y),就能很快想到不相邻的立方数之差是不可能是素数的:),,然后把y=x+1代入,得:p=3x^2+3x+1,所以可得判断条件为:①p-1必须能被3整除:②(p-1)/3必须能表示为两个相邻整数之积. #include<iostream> #inc…

HDU 1394 Minimum Inversion Number(线段树求最小逆序数对) ACM 题目地址:HDU 1394 Minimum Inversion Number 题意:  给一个序列由[1,N]构成.能够通过旋转把第一个移动到最后一个.  问旋转后最小的逆序数对. 分析:  注意,序列是由[1,N]构成的,我们模拟下旋转,总的逆序数对会有规律的变化.  求出初始的逆序数对再循环一遍即可了. 至于求逆序数对,我曾经用归并排序解过这道题:点这里.  只是因为数据范围是5000.所以全…

JAVA+大数搞了一遍- - 不是很麻烦- - /* HDU 6093 - Rikka with Number [ 进制转换,康托展开,大数 ] | 2017 Multi-University Training Contest 5 题意: 求L,R之间的好数的个数,好数要求在某个d(>=2)进制下数位是0到d-1的 分析: d 进制下好数的个数为 d!-(d-1)! ,且满足 d^(d-1) <= K <= d^d 可知 若 N > d^d 则 1-N 包含前 d-1 个进制的所有…

The kth great number Time Limit:1000MS     Memory Limit:65768KB     64bit IO Format:%I64d & %I64u Submit Status Practice HDU 4006 Description Xiao Ming and Xiao Bao are playing a simple Numbers game. In a round Xiao Ming can choose to write down a nu…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=1394 Minimum Inversion Number                        Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)                                            Total Submission(s): 10…

Minimum Inversion Number Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others) Total Submission(s): 17737    Accepted Submission(s): 10763 Problem Description The inversion number of a given number sequence a1, a2, ...,…

Balanced Number Problem Description A balanced number is a non-negative integer that can be balanced if a pivot is placed at some digit. More specifically, imagine each digit as a box with weight indicated by the digit. When a pivot is placed at some…