#include <stdio.h>
extern char * name[]; // imaginary array of pointers to page URLs
#define debug 0
extern int totalPageCount; // how many pages this Pentium knows.
void dup(int); // Accepts reports of pages with both words.
char * fwc(char *); // Find page data for a given word.
void ftwp(char *w1, char *w2) {char *cp = fwc(w1), *dp = fwc(w2);
  int c=*cp, d=*dp;
//This code searches for pages that contain both of the words
//identified by  w1 and w2.
// It is used when each word is so common that it occurs in 0.6% of all pages.
while(1) {// at this point c and d each hold the dense code for pages
// that contain respectively the two sought words.
if (debug) {
   if(c&255) printf("\"%s\" occurs in the page at %s\n", w1, name[c]);
   if(d&255) printf("\"%s\" occurs in the page at %s\n", w2, name[d]);}
     if (d < c) d += *++dp;
else if (c < d) c += *++cp;
else { // c == d and thus we are either at the end of the world
// or we have a page with both words
  if (c == totalPageCount) return; // No more interesting pages in this neighborhood.
  if (c&255) dup(c);
  d += *++dp; c += *++cp;
 }}
}
// This data structure requires perhaps 10 TB of RAM for the web,
// At $.10 per megabyte this comes to one M$ not including power, processors,
// other data structures etc.