Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 49991   Accepted: 13040 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true.…

Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 48624   Accepted: 12697 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true.…

题目 很简单,给一堆6元组,可以从任意位置开始往任意方向读,问有没有两个相同的6元组 题解 hash表入门题 先把一个六元组的积 + 和取模作为hash值,然后查表即可 期望\(O(n)\) #include<iostream> #include<cstdio> #include<cmath> #include<cstring> #include<algorithm> #define LL long long int #define Redge(…

Snowflake Snow Snowflakes Time Limit: 4000MS Memory Limit: 65536K Total Submissions: 37615 Accepted: 9882 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Your…

链接:Snowflake Snow Snowflakes 判断所有的雪花里面有没有相同的 每次把雪花每个角的值进行相加和相乘 之后hash #include<iostream> #include<algorithm> #include<cstring> #include<stdio.h> using namespace std; typedef long long LL; ; ,p=; ],head[maxn],nex[maxn]; int he(int *…

Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 48646   Accepted: 12703 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true.…

最近在对照省选知识点自己的技能树 今天是Hash 题面 大概是给定有n个6元序列 定义两个序列相等 当两个序列各自从某一个元素开始顺时针或者逆时针旋转排列能得到两个相同的序列 求这n个6元序列中是否有相等的序列 解释相等序列的样例 顺时针:如 1 2 3 4 5 6 与 2 3 4 5 6 1 相等 逆时针:如 1 2 3 4 5 6 与 6 5 4 3 2 1 相等 算法 对于各种类型的数列 字符串是否相等问题我们都可以用Hash解决 我们对一个序列A 定义其哈希值为 \(H(A) = (\s…

Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Your program will read information about a collection of snowflakes, and search for a pair that may be identica…

考察hash表: 每一个雪花都有各自的6个arm值,如果两个雪花从相同或者不同位置开始顺时针数或者逆时针数可以匹配上,那么这两个雪花就是相等的. 我们采用hash的方法,这样每次查询用时为O(1),总用时为O(n). hash的本质是把值映射到地址或者下标,如果不同的key值对应到相同的indice上的话,就需要进行chaining处理,吧indice指向一个链表,链表的每一个节点存储共享同一indice的不同key值. 因此问题的核心变成:吧相等的雪花映射到相同的indice上.这里雪花是一个…

吼哇! 关于开散列哈希: 哈希就是把xxx对应到一个数字的东西,可以理解成一个map<xxx, int>(是不是比喻反了) 我们要设计一个函数,这个函数要确保同一个东西能得到相同的函数值(废话) 然后在函数值域上开邻接表即可. 本人第一次写hash,还不是经典字符串hash而是雪花雪雪花(......) 那么接下来欣赏丑陋不堪的hash吧! (poj上C++过不了,RE,G++就过了,有剧毒) #include <cstdio> , P = ; ]; struct Snowflak…

http://poj.org/problem?id=3349 题意: 给出n片雪花留个角的长度,要求判断是否有一样的雪花. 思路: Hash表的应用. 首先将每个雪花所有角的总长计算出来,如果两片雪花相同的话那么总长也是相同的,然后加入vector容器当中,最后遍历vector数组,如果某个总长有大于1的雪花数,则有可能存在相同的雪花,此时需要比较这些雪花. #include <iostream> #include <stdio.h> #include <vector>…

首先声明代码并没有AC,内存超了 但我对此无能为力,有没有哪位大神好心教一下怎么写 哈希,然后比较花瓣数组,这些应该都没问题才对..唉.. 贴MLE代码 import java.util.*; public class POJ3349 { static int N = 1200007; public static class HashNode{ int[] num=null; HashNode next = null; } // hashlist[i]存储hash值为i的链表 static Ha…

题目链接. 分析: 哈希竟然能这么用.检查两片雪花是否相同不难,但如果是直接暴力,定会超时.所以要求哈希值相同时再检查. AC代码: #include <iostream> #include <cstdio> #include <cstdlib> #include <string> #include <algorithm> #include <vector> #include <map> #include <cstr…

题目链接:http://poj.org/problem?id=3349 题意:雪花有6个瓣,有n个雪花,输入每个雪花的瓣长,判断是否有一模一样的雪花(通过旋转或翻转最终一样,即瓣长对应相等).如果前面的雪花判断出有重复,则不需对后续的进行操作. 题解:直接将花瓣存在二维数组里面,然后每次新输入一个,再对之前的进行遍历判重.但是这种做法很低效,遍历花了很多时间.所以用哈希表,可直接访问是否存在重复,如果不重复,则用一维数组将雪花存起来(数组包含在结构体里),并将其"挂"在相应的哈希值(k…

哈希+挂链.可以用next数组挂链. ; type arr=..]of longint; var a,b:Array[..]of arr; next:Array[..]of longint; i,j,n,has,tot:longint; function hash(x:longint):longint; var i:longint; begin hash:=; do hash:=(hash*+a[x,i]*) mod p; inc(hash); end; function equa(a,b:ar…

POJ3349 Language: Snowflake Snow Snowflakes 题目:传送门 题解: 链表+hash的一道水题 填个坑补个漏... 代码: #include<cstdio> #include<cstring> #include<cstdlib> #include<cmath> #include<algorithm> using namespace std; typedef long long LL; ; ],snow[][…

http://poj.org/problem?id=3349 Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 37609   Accepted: 9878 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine…

Snowflake Snow Snowflakes poj-3349 题目大意:给出n片雪花,每片雪花有6个角,每个角有一个权值.如果两片雪花中能够各选出一个点,使得从该点顺时针或者逆时针转,得到的权值序列完全相符,那么我们就说这两片雪花是完全相同的. 注释:$1\le n\le 10^5$. 想法:其实并不是一道真正意义上的hash.我们对每个雪花进行处理:如果两个雪花a,b,满足: $\sum\limits_{i=1}^{6} a_i+\prod\limits_{i=1}^{6}a_i$相等…

Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 39324   Accepted: 10298 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true.…

Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 27312   Accepted: 7213 题目链接:http://poj.org/problem?id=3349 Description You may have heard that no two snowflakes are alike. Your task is to write a program to dete…

Snowflake Snow Snowflakes Time Limit: 4000MS Memory Limit: 65536K Total Submissions: 27598 Accepted: 7312 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Your…

Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 30512   Accepted: 8024 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Y…

相应POJ题目:点击打开链接 Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 33595   Accepted: 8811 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is…

Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 30529   Accepted: 8033 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Y…

Snowflake Snow Snowflakes Time Limit: 4000MS Memory Limit: 65536K Total Submissions: 34762 Accepted: 9126 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Your…

Snowflake Snow Snowflakes Time Limit: 4000MS   Memory Limit: 65536K Total Submissions: 35642   Accepted: 9373 Description You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Y…

[题目链接] http://poj.org/problem?id=3349 [算法] 哈希 若两片雪花相同,则它们六个角上的和一定相同,不妨令 H(A) = sigma(Ai) % P ,每次只要到哈希表里查是否出现相同雪花,即可 [代码] #include <algorithm> #include <bitset> #include <cctype> #include <cerrno> #include <clocale> #include &…

You may have heard that no two snowflakes are alike. Your task is to write a program to determine whether this is really true. Your program will read information about a collection of snowflakes, and search for a pair that may be identical. Each snow…

题目链接: http://poj.org/problem?id=3349 #include <stdio.h> #include <string.h> #include <iostream> using namespace std; ; struct Snow { ]; }snow[]; struct HashTable { struct Snow *data; struct HashTable *next; HashTable() { next = NULL; } }…

[题目大意] 已知多项式方程:a0+a1*x+a2*x^2+...+an*x^n=0.求这个方程在[1,m]内的整数解(n和m均为正整数). [思路] *当年考场上怒打300+行高精度,然而没骗到多少orz 然而正解只有60+行 [前铺]f(n) mod p=f(n mod p) mod p 取四个素数,分别对每个ai取模.先预处理x=0..p-1的情况,直接代入多项式计算即可.再在O(m)时间内检验1..m,对于≥p的利用前铺公式可得.如果模四个素数结果均能得到0,说明这个数是方程的解. P.…