·天新网首页·加入收藏·设为首页·网站导航
数码笔记本手机摄像机相机MP3MP4GPS
硬件台式机网络服务器主板CPU硬盘显卡
办公投影打印传真
家电电视影院空调
游戏网游单机动漫
汽车新车购车试驾
下载驱动源码
学院开发设计
考试公务员高考考研
业界互联网通信探索
您现在的位置:天新网 > 软件开发
POJ 2418 Hardwood Species (二叉搜索树)
http://www.21tx.com 2014年01月21日 CSDN 帆帆帆帆帆帆帆帆帆帆


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


题意:给定一些名称,求出每个名称出现频率

思路:二叉搜索树。。 节点多保存一个value次数

代码:

#include <stdio.h>
#include <string.h>
char ci[35];
int n = 0;
  
struct Node {
    char c[35];
    int num;
    struct Node *l;
    struct Node *r;
    Node () {
        memset(c, 0, sizeof(c));
        l = NULL;
        r = NULL;
        num = 1;
    }
};
  
Node *T;
  
void Insert(Node *T) {
    if (!strcmp(ci, T->c)) {
        T->num ++;
        return;
    }
    else if (strcmp(ci, T->c) > 0) {
        if (T->r != NULL)
            Insert(T->r);
        else {
            T->r = new Node;
            strcpy(T->r->c, ci);
        }
    }
    else {
        if (T->l != NULL)
            Insert(T->l);
        else {
            T->l = new Node;
            strcpy(T->l->c, ci);
        }
    }
}
  
void print(Node *T) {
    if (T->l != NULL)
        print(T->l);
    if (T->num != 0)
        printf("%s %.4lfn", T->c, (double)T->num * 100 / (double)n);
    if (T->r != NULL)
        print(T->r);
}
int main() {
    T = new Node;
    T->num = 0;
    while (gets(ci)) {
        n ++;
        Insert(T);
    }
    print(T);
    return 0;
}



上一篇: UVA 825 Walking on the Safe Side(记忆化搜索)
下一篇: UVA 10029 - Edit Step Ladders(记忆化搜索)

关于我们 | 联系我们 | 加入我们 | 广告服务 | 投诉意见 | 网站导航
Copyright © 2000-2011 21tx.com, All Rights Reserved.
晨新科技 版权所有 Created by TXSite.net