flags.cpp

来自「Think in C++文中代码实现」· C++ 代码 · 共 80 行

// File from page 186 in "Thinking in C++" by Bruce Eckel
//////////////////////////////////////////////////
// From the compressed package ECKELT02.ZIP 4/11/95
// (Original ECKELT01.ZIP dated 2/21/95)
// Copyright (c) Bruce Eckel, 1995 
// Source code file from the book "Thinking in C++", 
// Prentice Hall, 1995, ISBN: 0-13-917709-4
// All rights reserved EXCEPT as allowed by the following 
// statements: You may freely use this file for your own 
// work, including modifications and distribution in 
// executable form only. You may copy and distribute this 
// file, as long as it is only distributed in the complete 
// (compressed) package with the other files from this 
// book and you do not remove this copyright and notice. 
// You may not distribute modified versions of the source 
// code in this package. This package may be freely placed 
// on bulletin boards, internet nodes, shareware disks and 
// product vendor disks. You may not use this file in 
// printed media without the express permission of the 
// author. Bruce Eckel makes no 
// representation about the suitability of this software 
// for any purpose. It is provided "as is" without express 
// or implied warranty of any kind. The entire risk as to 
// the quality and performance of the software is with 
// you. Should the software prove defective, you assume 
// the cost of all necessary servicing, repair, or 
// correction. 
// If you think you've found an error, please 
// email all modified files with loudly commented changes 
// to: [e-mail] (please use the same 
// address for non-code errors found in the book).
//////////////////////////////////////////////////

//: FLAGS.CPP -- List of true/false flags
#include <stdio.h>
#include <string.h>
#include <assert.h>
#define FSIZE 100
#define TRUE 1
#define FALSE 0

class flags {
  unsigned char f[FSIZE];
public:
  flags();
  void set(int i);
  void clear(int i);
  int read(int i);
  int size();
};

flags::flags() {
  memset(f, FALSE, FSIZE);
}

void flags::set(int i) {
  assert(i >= 0 && i < FSIZE);
  f[i] = TRUE;
}

void flags::clear(int i) {
  assert(i >= 0 && i < FSIZE);
  f[i] = FALSE;
}

int flags::read(int i) {
  assert(i >= 0 && i < FSIZE);
  return f[i];
}

int flags::size() { return FSIZE; }

main() {
  flags fl;
  for(int i = 0; i < fl.size(); i++)
    if(i % 3 == 0) fl.set(i);
  for(int j = 0; j < fl.size(); j++)
    printf("fl.read(%d)= %d\n", j, fl.read(j));
}