less_than.cpp

/**
 * Boost Software License - Version 1.0 - August 17th, 2003
 * Permission is hereby granted, free of charge, to any person
 * or organization obtaining a copy of the software and
 * accompanying documentation covered by this license
 * (the "Software") to use, reproduce, display, distribute,
 * execute, and transmit the Software, and to prepare derivative
 * works of the Software, and to permit third-parties to whom the
 * Software is furnished to do so, all subject to the following:
 *
 * The copyright notices in the Software and this entire statement,
 * including the above license grant, this restriction and the following
 * disclaimer, must be included in all copies of the Software, in whole or
 * in part, and all derivative works of the Software, unless such copies
 * or derivative works are solely in the form of machine-executable
 * object code generated by a source language processor.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, TITLE AND
 * NON-INFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR ANYONE
 * DISTRIBUTING THE SOFTWARE BE LIABLE FOR ANY DAMAGES OR OTHER LIABILITY,
 * WHETHER IN CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

#include <istream>
#include <ostream>

#include "../bigint.hpp"

namespace libbig
{
  bool largeInt:: operator < (const largeInt& z) {
    // sign = 1: positive number
    // sign = 0: negative number
    // flip if its reverse

    bool NEGATIVE = 0;
    bool POSITIVE = 1;

    if (this->sign == NEGATIVE) {
      if (z.sign == POSITIVE){
        return true;
      } else if (z.sign == NEGATIVE){
        if (this->number.length() > z.number.length()){
          return true;
        }
        if (this->number.length() < z.number.length()){
          return false;
        }
        for(int i = 0; i < this->number.length(); i++) {
          if (this->number[i] < z.number[i]) {
            return false;
          }
        }
      }
    } else if (this->sign == POSITIVE) {
      if (z.sign == NEGATIVE){
        return false;
      } else if (z.sign == POSITIVE){
        if (this->number.length() < z.number.length()){
          return true;
        }
        if (this->number.length() > z.number.length()){
          return false;
        }
        for(int i = 0; i < this->number.length(); i++) {
          if (this->number[i] > z.number[i]) {
            return false;
          }
        }
      }
    }
    return false;
  }
} // namespace libbig