数据结构实验之查找三:树的种类统计
Time Limit: 400 ms Memory Limit: 65536 KiB
Problem Description
随着卫星成像技术的应用,自然资源研究机构可以识别每一个棵树的种类。请编写程序帮助研究人员统计每种树的数量,计算每种树占总数的百分比。
Input
输入一组测试数据。数据的第1行给出一个正整数N (n <= 100000),N表示树的数量;随后N行,每行给出卫星观测到的一棵树的种类名称,树的名称是一个不超过20个字符的字符串,字符串由英文字母和空格组成,不区分大小写。
Output
按字典序输出各种树的种类名称和它占的百分比,中间以空格间隔,小数点后保留两位小数。
Sample Input
2 This is an Appletree this is an appletree
Sample Output
this is an appletree 100.00%
Hint
Source
xam
二叉排序树
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct node
{
char str[22];
int cnt;
struct node *left;
struct node *right;
};
int n;
struct node *creat(struct node *head, char *s)
{
if(!head)
{
head = (struct node *)malloc(sizeof(struct node));
head -> cnt = 1;
strcpy(head -> str, s);
head -> left = NULL;
head -> right = NULL;
}
else
{
int k;
k = strcmp(head -> str, s);
if(k > 0)
{
head -> left = creat(head -> left, s);
}
else if(k < 0)
head -> right = creat(head -> right, s);
else
head -> cnt++;
}
return head;
};
void show(struct node *head)
{
if(head)
{
show(head -> left);
printf("%s %.2lf%c\n", head -> str, head -> cnt * 100.0 / n, '%');
show(head -> right);
}
}
int main()
{
struct node *head = NULL;
char s[22];
scanf("%d", &n);
getchar(); //换行了
int i, j;
for(i = 0; i < n; i++)
{
gets(s);
for(j = 0; s[j]; j++)
{
if(s[j] >= 'A' && s[j] <= 'Z') // 都改成小写
s[j] += 32;
}
head = creat(head, s);
}
show(head);
return 0;
}