C++相同的程序:两个不同的结果.也许是由于运营商>>？

Question

我需要你对错误的看法.

在家里,我用Bloodsheed编写了一个程序并得到了想要的结果.该程序的目的是显示源文件中的行以输出具有特定宽度的文本.源文件无法逐行分析.相反,它应该使用char和string word来读取.

然后我去了uni使用TextPad和Borland提交我的程序:输出是不同的:单词之间的空格和一些行尾字符被忽略.我不明白发生了什么.我花了整整一天的时间没有成功.编译器使用不同的运算符>>来读取字符串吗？看起来在第一种情况下,它在第二种情况下在空格或行尾字符之前停止它丢弃它们.你有关于这个问题的建议吗？

在家里成功的输出是:

Max line length: 40

___Inglis_(1994)_describes_it_thus:

"For_output_of___floating-point_numbers,
the_format_strings_used_by_printf_may
include_%f_or_%e_(or_%g,_which_we_will
ignore).__These_have_much_in_common_with
%i:

____"A_minus_sign_indicates_left
justification,_a_plus_sign_indicates
that_the_converted_value_will_start_with
a_plus_sign_if_it_is_positive,_and_a
minimum_field_width_and/or_a_precision
may_be_specified.

在大学:

Max line length: 40

___Inglis(1994)describesitthus:

"Foroutputof__floating-pointnumbers,the
formatstringsusedbyprintfmayinclude%for
%e(or%g,whichwewillignore)._Thesehave
muchincommonwith%i:
____"Aminussignindicatesleft
justification,aplussignindicatesthatthe
convertedvaluewillstartwithaplussignifit
ispositive,andaminimumfieldwidthand/ora
precisionmaybespecified.

出错的功能:

void Text::display(ofstream & out)
{ ifstream from(infileName.c_str());
  if (from.fail())
  { cerr<<infileName<<" not open\n";
    exit(1);
  }
  out<<"Max line length: "<<lineLength<<endl<<endl;
  string s, w;   //s stands for space, w for word
  char l;        //l stands for letter
  int c=0;       //c syands for count
  while(true)
  { if(static_cast<int>(w.length())>0)
    {  if(lineLength<w.length())
       { cerr <<"The line length "<<lineLength
             <<" is not long enough.\n"<<"The longuest word is "
             <<w<<" and has "<<w.length()
             <<" letters.\n";
         exit(1);
       }
       c+=w.length();
       out<<w;
       w.erase();
    }
    from.get(l);
    if (from.fail())
    {  out<<endl;
       break;
    }
    if (l=='\n')
    {  out<<l;
       s.erase();
       c=0;
       continue;
    }
    while (l==' ')
    {  s.push_back('_');
       c++;
       from.get(l);
    }
    if (l=='\n')
    {  out<<l;
       s.erase();
       c=0;
       continue;
    }
    from.putback(l);
    from>>w;
    c+=w.length();
    if (lineLength<c)
    {  out<<endl;
       s.erase();
       c=0;
    }
    else if(w.length()>0)
    {  out<<s<<w;
       w.erase();
       s.erase();
    }
  }
}

Answer 1

这是不同换行表示的症状.

在"home",你的换行符是LF('\n'或0x0A).

在"uni",您的换行符是CR + LF('\r\n'或0x0D0A).

您的代码仅允许LF换行符.

作为旁白...

string s, w;   //s stands for space, w for word
char l;        //l stands for letter
int c=0;       //c syands for count

C++允许标识符长于单个字符.以下内容更具表现力,无需注释,并且可以更轻松地维护代码.

std::string space, word;
char letter;
int count = 0;