单词统计word count

#include <stdio.h>

#define F_LETTER     0
#define F_SPACE	     1

#define IS_LETTER( _ch_ )	(_ch_ >= 'a' && _ch_ <= 'z' || _ch_ >= 'A' && _ch_ <= 'Z')
 
int main()
{
	char *str = "hello,world,a.a*a(a";
	int flag = F_SPACE, n_word = 0;
	char *p = str;

	for(p = str; '\0' != *p; p ++)
	{
		if(IS_LETTER(*p))
		{
			n_word += flag;
			flag = F_LETTER;
		}
		else
		{
			flag = F_SPACE;
		}
	}
	printf("the number of word = %d\n", n_word);
	return 0;
}