POJ 2418 Hardwood Species

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.

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

这道题对我来说又是看不懂题意系列，简直是菜出了新境界。

题意是给你每行一种树的名字，最后按字典序输出每种树所占树木总数的百分比。

用map记录一下就好了。

这道题让我学到了getline要你自己去手动停止才会输出结果，以及POJ输出真的是要用%f不要用%lf。血的教训。

（刚刚才发现自己没贴代码，真的智障）

AC代码：

#include<iostream>#include<algorithm>#include<cstring>#include<map>#include<cstdio>using namespace std;map<string,int> myMap;map<string,int> :: iterator it;string s;int main(){    int cmp=0;    while(getline(cin,s))    {        myMap[s]++;        cmp++;    }    string name;    int cnt;    for(it=myMap.begin();it!=myMap.end();it++)    {        name=it->first;        cnt=it->second;        printf("%s %.4f\n",name.c_str(),double(cnt)*100/double(cmp));    }    return 0;}