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#include<stdio.h>
#include<ctype.h>
#include<string.h>
struct key
{
char *word;
int count;
} keytab[] = {
"auto", 0,
"break", 0,
"case", 0,
"char", 0,
"const", 0,
"continue", 0,
"default", 0,
"do", 0,
"double", 0,
"else", 0,
"enum", 0,
"extern", 0,
"float", 0,
"for", 0,
"goto", 0,
"if", 0,
"int", 0,
"long", 0,
"register", 0,
"return", 0,
"short", 0,
"signed", 0,
"sizeof", 0,
"static", 0,
"struct", 0,
"switch", 0,
"typedef", 0,
"union", 0,
"unsigned", 0,
"void", 0,
"volatile", 0,
"while", 0
};
#define BUFSIZE 100
#define MAXWORD 100
#define NKEYS (sizeof keytab / sizeof(keytab[0]))
int getword(char *, int);
struct key *binsearch1(char *, struct key *, int);
char buf[BUFSIZE];
int bufp=0;
int main()
{
char word[MAXWORD];
struct key *p;
while (getword(word, MAXWORD) != EOF)
if (isalpha(word[0]))
if ((p = binsearch1(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 *binsearch1(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;
}
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];
}
int getch(void)
{
return (bufp > 0) ? buf[--bufp] : getchar();
}
void ungetch(int c)
{
if (bufp >= BUFSIZE) printf("ungetch: too many characters\n");
else
buf[bufp++]=c;
}
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