2405073_ac_15ms_176k.c

北大大牛代码 1240道题的原代码 超级权威

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define INIT (Tree *)malloc(sizeof(Tree))
typedef struct node
{
	int app;
	char word[100];
	struct node *l, *r;
}Tree;

Tree *head;
int mark = 1, max = 1;
int is(char ch)
{
	if(ch<='Z'&&ch>='A')
		return 1;
	if(ch>='a'&&ch<='z')
		return 1;
	if(ch<='9'&&ch>='0')
		return 1;
	return 0;
}

void insert(char word[])
{
	Tree *s, *p;

	if(mark)
	{
		head = INIT;
		head->app = 1;
		mark = 0;
		strcpy(head->word,word);
		head->l = head->r = NULL;
	}
	else
	{
		s = head;
		p = INIT;
		p->app = 1;
		strcpy(p->word,word);
		p->l = p->r = NULL;
		while(s)
		{
			if(strcmp(s->word,word)>0)
				if(s->l)
					s = s->l;
				else
				{
					s->l = p;
					break;
				}
				else
					if(strcmp(s->word,word)<0)
						if(s->r)
							s = s->r;
						else
						{
							s->r = p;
							break;
						}
						else
						{
							s->app++;
							if(s->app>max)
								max = s->app;
							break;
						}
		}
	}
}

void solve(Tree *s)
{
	if(s->l)
		solve(s->l);
	if(s->app==max)
		puts(s->word);
	if(s->r)
		solve(s->r);
}

int main()
{
	int i;
	char word[100], tmp[100];

	while(scanf("%s",word)==1)
	{
		for(i = strlen(word)-1; i >= -1; i--)
		{
			if(i>-1&&word[i]<='Z'&&word[i]>='A')
				word[i] += 32;
			if(i==-1||!is(word[i]))
			{
				strcpy(tmp,&word[i+1]);
				word[i] = '\0';
				if(strlen(tmp))
					insert(tmp);
			}
		}
	}
	printf("%d occurrences\n",max);
	solve(head);
	return 1;
}