poj 2418 Hardwood Species 字典树
来源:互联网 发布:icepak软件下载 编辑:程序博客网 时间:2024/05/24 03:01
Hardwood Species
Description
Hardwoods are the botanical group of trees that have broad leaves, produce a fruit or nut, and generally go dormant in the winter.
America's temperate climates produce forests with hundreds of hardwood species -- trees that share certain biological characteristics. Although oak, maple and cherry all are types of hardwood trees, for example, they are different species. Together, all the hardwood species represent 40 percent of the trees in the United States.
On the other hand, softwoods, or conifers, from the Latin word meaning "cone-bearing," have needles. Widely available US softwoods include cedar, fir, hemlock, pine, redwood, spruce and cypress. In a home, the softwoods are used primarily as structural lumber such as 2x4s and 2x6s, with some limited decorative applications.
Using satellite imaging technology, the Department of Natural Resources has compiled an inventory of every tree standing on a particular day. You are to compute the total fraction of the tree population represented by each species.
America's temperate climates produce forests with hundreds of hardwood species -- trees that share certain biological characteristics. Although oak, maple and cherry all are types of hardwood trees, for example, they are different species. Together, all the hardwood species represent 40 percent of the trees in the United States.
On the other hand, softwoods, or conifers, from the Latin word meaning "cone-bearing," have needles. Widely available US softwoods include cedar, fir, hemlock, pine, redwood, spruce and cypress. In a home, the softwoods are used primarily as structural lumber such as 2x4s and 2x6s, with some limited decorative applications.
Using satellite imaging technology, the Department of Natural Resources has compiled an inventory of every tree standing on a particular day. You are to compute the total fraction of the tree population represented by each species.
Input
Input to your program consists of a list of the species of every tree observed by the satellite; one tree per line. No species name exceeds 30 characters. There are no more than 10,000 species and no more than 1,000,000 trees.
Output
Print the name of each species represented in the population, in alphabetical order, followed by the percentage of the population it represents, to 4 decimal places.
Sample Input
Red AlderAshAspenBasswoodAshBeechYellow BirchAshCherryCottonwoodAshCypressRed ElmGumHackberryWhite OakHickoryPecanHard MapleWhite OakSoft MapleRed OakRed OakWhite OakPoplanSassafrasSycamoreBlack WalnutWillow
Sample Output
Ash 13.7931Aspen 3.4483Basswood 3.4483Beech 3.4483Black Walnut 3.4483Cherry 3.4483Cottonwood 3.4483Cypress 3.4483Gum 3.4483Hackberry 3.4483Hard Maple 3.4483Hickory 3.4483Pecan 3.4483Poplan 3.4483Red Alder 3.4483Red Elm 3.4483Red Oak 6.8966Sassafras 3.4483Soft Maple 3.4483Sycamore 3.4483White Oak 10.3448Willow 3.4483Yellow Birch 3.4483
Hint
This problem has huge input, use scanf instead of cin to avoid time limit exceeded.
题意:给出一组以EOF结束的字符串,统计每个字符串出现的频率,按照字典序输出
数据结构:字典树
思路:每个单词的结束字符记录自己所表示的单词的出现次数num,还要记录单词的总数sum,对字典树进行深度优先遍历,每递归一层就记录这一层的字母,直到遇到单词的结束标识,即num!=0,此时输出这个单词,并且用num/sum×100得到频率,输出即可。
#include <iostream>#include <stdio.h>#define MAX 256using namespace std;struct trie{ int num; trie *next[MAX];};trie *root=new trie;char words[40];int sum;void insert_trie(char *str){ trie *p,*newnode; p=root; for(int i=0; str[i]!='\0'; i++) { if(p->next[(int)str[i]]==NULL) { newnode=new trie; for(int j=0; j<MAX; j++) newnode->next[j]=NULL; newnode->num=0; p->next[(int)str[i]]=newnode; p=newnode; } else { p=p->next[(int)str[i]]; } } p->num++; sum++;}void dfs(trie *p,int cur){ for(int i=0; i<MAX; i++) { if(p->next[i]!=NULL) { words[cur]=(char)i; if(p->next[i]->num!=0) { words[cur+1]='\0'; printf("%s %.4f\n",words,(double)p->next[i]->num/(double)sum*100); p->num=0; } dfs(p->next[i],cur+1); } }}int main(){ int i; for(i=0; i<MAX; i++) root->next[i]=NULL; root->num=0; sum=0; while(gets(words)) { insert_trie(words); //printf("sum=%d\n",sum); } dfs(root,0); return 0;}
0 0
- POJ 2418 Hardwood Species (字典树)
- POJ 2418 Hardwood Species(字典树)
- [字典树] poj 2418 Hardwood Species
- 【字典树】POJ 2418 Hardwood Species
- POJ 2418 Hardwood Species(字典树)
- POJ 2418 Hardwood Species (字典树||MAP)
- POJ-2418-Hardwood Species-字典树
- POJ 2418 Hardwood Species(字典树)
- POJ---2418-Hardwood Species(字典树)
- poj 2418 Hardwood Species 字典树
- POJ 2418 Hardwood Species【字典树 / map】
- POJ Hardwood Species 2418(字典树)
- Hardwood Species 字典树 poj 2418
- poj 2418 Hardwood Species(字典树)
- (模板题)poj 2418 Hardwood Species(字典树)
- POJ 2418 Hardwood Species (字典树 || map)
- poj 2814(字典树Hardwood Species)
- Hardwood Species(字典树)
- MySql中的存储过程
- 你能当领导吗
- Jquery AutoComplete的使用方法实例
- js 获取路径中参数值
- Java锁的种类以及辨析(三):阻塞锁
- poj 2418 Hardwood Species 字典树
- 【Android学习之道】 四大组件之广播接收器Broadcast Receiver
- 倒计时页面跳转、jsp 中如何使页面停留几秒后再转向其他页面
- spark 点滴:多路输出,自定义分区
- 双网卡不能同时上网
- Java锁的种类以及辨析(四):可重入锁
- PHP http_build_query()函数
- MySql自定义函数
- IOS中,两个APP之间的跳转!