Hardwood Species
| Time Limit: 10000MS | Memory Limit: 65536K | |
| Total Submissions: 19428 | Accepted: 7658 |
http://poj.org/problem?id=2418
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 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
Sample Output
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
Hint
This problem has huge input, use scanf instead of cin to avoid time limit exceeded.
Source
/*
用二叉排序树 做的
G++ WA；
C++ AC；
数据结构（严蔚敏）P228
*/
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
using namespace std;
typedef char Keytype;//关键字的类型
typedef char Elemtype;//插入元素的类型
typedef struct Bitnode
{
Keytype data[50];//排序二叉树的节点信息
int count;
struct Bitnode *lchild;//左孩子指针
struct Bitnode *rchild;//右孩子指针
}Bitnode,*Bitree;
int sum;
int EQ(Keytype a[],Keytype b[])//判断 a==b?
{
if(strcmp(a,b)==0)
return 1;
else
return 0;
}
int LT(Keytype a[],Keytype b[])//判断 a<b?
{
if(strcmp(a,b)<0)
return 1;
else
return 0;
}
int SearchBST(Bitree T,Keytype key[],Bitree f,Bitree &p)
{
if(!T)//查找不成功
{
p=f;
return 0;
}
else if(EQ(key,T->data))//查找成功
{
T->count++;
p=T;
return 1;
}
else if(LT(key,T->data))
return SearchBST(T->lchild,key,T,p);//在左子树中继续查找
else
return SearchBST(T->rchild,key,T,p);//在右子树中继续查找
}
void InsertBST(Bitree &T,Elemtype e[])//插入操作
{
Bitree p;
if(!SearchBST(T,e,NULL,p))//当查找不成功时进行插入操作
{
Bitree s=(Bitree)malloc(sizeof(Bitnode));//申请动态存储空间
s->lchild=s->rchild=NULL;
s->count=1;
strcpy(s->data,e);
if(!p)
T=s;
else if(LT(e,p->data))
p->lchild=s;
else
p->rchild=s;
}
}
void Inodertraverse(Bitree T)//中序遍历排序二叉树
{
if(T)
{
Inodertraverse(T->lchild);
printf("%s %.4lf\n",T->data,100*((T->count*1.0)/(sum*1.0)));
Inodertraverse(T->rchild);
}
}
char s[50];
void CreateBST(Bitree &T)//创建排序二叉树
{
while(gets(s)&&s[0]!=‘\0‘)
{
InsertBST(T,s);
sum++;
}
}
int main()
{
Bitree T=NULL;
CreateBST(T);
Inodertraverse(T);
return 0;
}