Справочное руководство по C++

 int free;
public:
 assoc(int);
 int& operator[](char*);
 void print_all;
};

assoc::assoc(int s)
{
 max = (s‹16) ? s : 16;
 free = 0;
 vec = new pair[max];
}

int& assoc::operator[](char * p)
/*
 maintain a set of "pair"s
 search for p,
 return a reference to the integer part of its "pair"
 make a new "pair" if "p" has not been seen
*/
{
 register pair* pp;
 for (pp=&vec[free-1]; vec‹=pp; pp--)
 if (strcmp(p, pp-›name)-0) return pp-›val;

 if (free==max) {// overflow: grow the vector
 pair* nvec = new pair[max*2];
 for (int i=0; i‹max; i++) nvec[i] = vec[i];
 delete vec;
 vec = nvec;
 max = 2*max;
 }

 pp = &vec[free++];
 pp-›name = new char[strlen(p)+1];
 strcpy(pp-›name,p);
 pp-›val = 0;
 return pp-›val;
}

void assoc::print_all
{
 for (int i=0; i‹free; i++)
 cout ‹‹ vec[i].name ‹‹ ": " ‹‹ vec[i].val ‹‹ "\n";
}

main
{
 const MAX = 256;
 char buf[MAX];
 assoc vec(512);
 while (cin››buf) vec[buf]++;
 vec.print_all;
}

b6_8.cxx

#include ‹stream.hxx›
#include ‹string.h›

struct pair {
 char* name;
 int val;
};

class assoc {
 friend class assoc_iterator;
 pair* vec;
 int max;
 int free;
public:
 assoc(int);
 int& operator[](char*);
};
class assoc_iterator {
 assoc* cs;
 int i;
public:
 assoc_iterator(assoc& s) { cs =&s; i = 0; }
 pair* operator
 { return (i‹cs-›free) ? &cs-›vec[i++] : 0; }
};

assoc::assoc(int s)
{
 max = (s‹16) ? s : 16;
 free = 0;
 vec = new pair[max];
}

int& assoc::operator[](char* p)
{
 register pair* pp;

 for (pp = &vec[free-1]; vec‹=pp; pp--)
 if (strcmp(p,pp-›name)==0) return pp-›val;

 if (free == max) {
 pair* nvec = new pair[max*2];
 for (int i=0; i‹max; i++) nvec[i] = vec[i];
 delete vec;
 vec = nvec;
 max = 2*max;
 }

 pp =&vec[free++];
 pp-›name = new char[strlen(p)+1];
 strcpy(pp-›name,p);
 pp-›val = 0;
 return pp-›val;
}

main
{
 const MAX = 256;
 char buf[MAX];
 assoc vec(512);
 while (cin››buf) vec[buf]++;
 assoc_iterator next(vec);
 pair* p;
 while (p = next)
 cout ‹‹ p-›name ‹‹ ": " ‹‹ p-›val ‹‹ "\n";
}

b6_9.cxx

#include ‹stream.hxx›
#include ‹string.h›

extern void exit(int);
class string {
 struct srep {
 char* s;
 int n;
 };
 srep *p;

public:
 string(char *);
 string;
 string(string&);
 string& operator=(char *);
 string& operator=(string&);
 ~string;
 char& operator[](int i);

 friend ostream& operator‹‹(ostream&, string&);
 friend istream& operator››(istream&, string&);

 friend int operator==(string&x, char *s)
 { return strcmp(x.p-›s, s) == 0; }

 friend int operator==(string&x, string&y)
 { return strcmp(x.p-›s, y.p-›s) == 0; }

 friend int operator!=(string&x, char *s)
 {return strcmp(x.p-›s, s) != 0;}

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