#include <stdio.h>
#include <ctype.h>
#include <string.h>
#define MAXWORD 100
#define NKEYS 11


struct key {
	char *word;
	int count;
	}; 
struct key keytab [] = {
	"auto", 0,
	"break", 0,
	"case", 0,
	"char", 0,
	"const", 0,
	"continue", 0,
	"default", 0,
	"unsigned", 0,
	"void", 0,
	"volatile", 0,
	"while", 0
	};

int getword(char *word, int lim)
{
	int c, getch(void);
	void ungetch(int);
	char *w = word;
	while (isspace(c = getch()))
		;
	if (c != EOF)
		*w++ = c;
	if (!isalpha(c)) {
		*w = '\0';
		return c;
	}
	for ( ; --lim > 0; w++)
		if (!isalnum(*w = getch())){
			ungetch(*w);
			break;
		}
	*w = '\0';
	return word[0];
}



/* count C keywords; pointer version */
main()
{
	char word[MAXWORD];
	struct key *p;
	
	while (getword(word, MAXWORD) != EOF)
		if (isalpha(word[0]))
			if((p=binsearch(word,keytab,NKEYS)) != NULL)
			p->count++;
		for (p = keytab; p < keytab + NKEYS; p++)
		 if (p-> count > 0)
		 	printf("%4d %s\n", p->count, p->word);
		return 0;
}

struct key *binsearch(char *word, struct key *tab, int n)
{
	int cond;
	struct key *low = &tab[0];
	struct key *high = &tab[n];
	struct key *mid;
	
	while (low < high) {
		mid = low + (high-low) / 2;
		if ((cond = strcmp(word, mid->word)) < 0 )
		 high = mid;
		else if (cond > 0 )
			low = mid + 1;
 		else
			return mid;
		}
		return NULL;
}