POJ-2418(BST)
2418:Hardwood Species
- 时间限制:
- 10000ms
- 内存限制:
- 65536kB
- 描述
- 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. - 输入
- 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.
- 输出
- 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.
- 样例输入
-
Red Alder Ash Aspen Basswood Ash Beech Yellow Birch Ash Cherry Cottonwood Ash Cypress Red Elm Gum Hackberry White Oak Hickory Pecan Hard Maple White Oak Soft Maple Red Oak Red Oak White Oak Poplan Sassafras Sycamore Black Walnut Willow
- 样例输出
-
Ash 13.7931 Aspen 3.4483 Basswood 3.4483 Beech 3.4483 Black Walnut 3.4483 Cherry 3.4483 Cottonwood 3.4483 Cypress 3.4483 Gum 3.4483 Hackberry 3.4483 Hard Maple 3.4483 Hickory 3.4483 Pecan 3.4483 Poplan 3.4483 Red Alder 3.4483 Red Elm 3.4483 Red Oak 6.8966 Sassafras 3.4483 Soft Maple 3.4483 Sycamore 3.4483 White Oak 10.3448 Willow 3.4483 Yellow Birch 3.4483
- 提示
- This problem has huge input, use scanf instead of cin to avoid time limit exceeded.
#include"iostream" #include"cstring" #include"stdio.h" using namespace std; class Tree{public:float n;char name[31];Tree *lchild,*rchild;}; char newchar[31]; bool flag; int count=0;//总共输入name的数量 Tree *myTree=NULL; void insert(Tree* pass){Tree* alias=pass;Tree* temp=NULL;//(1)起指示空数作用;(2)当前树中未找到当前插入值情况下,保存跳出while(pass!=NULL)时候pass的叶子(需要结合flag做后续处理)flag=false;while(alias!=NULL){if(strcmp(alias->name,newchar)==0){alias->n++;return;}else{temp=alias;if(strcmp(alias->name,newchar)>0){alias=alias->lchild;}else{alias=alias->rchild;}flag=true;}}if(temp==NULL)//myTree为空树,直接对之进行处理//(事实上跟下面if(flag==true)直接对alias进行处理也是可以的,因为alias并未做任何加工处理){myTree=new Tree;myTree->n=1;strcpy(myTree->name,newchar);myTree->lchild=NULL;myTree->rchild=NULL;}else{if(flag==true)//进入过while循环并且没有return退出;需要新增叶子{alias=new Tree;alias->n=1;strcpy(alias->name,newchar);alias->lchild=NULL;alias->rchild=NULL;}if(strcmp(temp->name,newchar)>0)//并且将新叶子与原来叶子相连(即temp){temp->lchild=alias;}else{temp->rchild=alias;}}//end Big else} void show(Tree* pass)//采用中序输出{if(pass!=NULL){show(pass->lchild);cout<<pass->name<<" ";printf("%.4f\n",100*pass->n/count);show(pass->rchild);}} int main(){while(gets(newchar)){count++;insert(myTree);}show(myTree);}