Question

我的代码的要点是能够在文本中的某处输入带有blank-n的文件。假设将blank-N更改为用户提示的代码，例如（blank-N）= noun并要求用户输入名词但由于某种原因我得到了该错误所以这是我的代码：

    //Author:
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#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
using std::string;
using namespace std;

string getWord(ifstream &Infile, char &ch);
void getFilename(ifstream &Infile);
void getOutfile(ofstream &Outfile);
void putWord(ostream &Outfile,string word, char space);
string replacement(string word,std::string);
void printprompt(int i);
int main()
{
  ifstream filename;
  ofstream outfile;
  string file;
  string word;
  char ch;
  getFilename(filename);
  getOutfile(outfile);
  while(!filename.eof())
    {
      file =getWord(filename,ch);

      putWord(outfile,file,ch);
    }
  filename.close();
  outfile.close();
  return 0;
}

string getWord(ifstream &Infile, char &ch)
{
  string wrd = "";

  Infile.get(ch);
  while(ch !=' '&& ch != '\n' && !Infile.eof())
    {
      wrd.append(1,ch);
      Infile.get(ch);
    }
  return wrd;
}

void getFilename(ifstream &Infile)
{
  string filename;
  cout<<"File for input: ";
  cin >>filename;

  Infile.open(filename.c_str());
  if (Infile.fail())
    {
      cout << "Cannot open"<<filename<<endl;
      exit(0);
    }
}

void getOutfile(ofstream &Outfile)
{
  string filename;
  cout<<"file for output: ";
  cin>>filename;
  Outfile.open(filename.c_str());
  if(Outfile.fail())
    {
      cout<< "Cannot open"<<Outfile<<endl;
      exit(0);
    }
}

void putWord(ofstream &Outfile,string word, char c)
{

  Outfile << word;
  if (c =='\n')
    Outfile<<endl;
  else
    Outfile<<" ";
}
string replacement(string word)
{
  string key[5]={"blank-N", "blank-A","blank-V","blank-P","blank-D"};
  for(int i =0; i<5;i++)
    {
      if(word.compare(key[i]))
        {
          printprompt(i);
          cin>>word;
        }

      return word;
    }
}
void printprompt(int i)
{
  switch(i)
    {
    case 0:
      cout<<"Please enter a noun";
      break;
    case 1:
      cout<<"Please enter an adjective";
      break;
    case 2:
      cout<<"Please enter a verb";
      break;
    case 3:
      cout<<"Please enter a place";
      break;
  default:;

    }
}

我似乎得到了这个错误：

    Undefined                       first referenced
 symbol                             in file
putWord(std::basic_ostream<char, std::char_traits<char> >&, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, char)/var/tmp//ccdj0m4f.o
ld: fatal: Symbol referencing errors. No output written to a.out
collect2: ld returned 1 exit status

我不知道如何防止此错误发生。

Answer 1

编译器告诉您该定义与实现不匹配。在这种情况下，参数类型不匹配。

您的定义：

void putWord(ostream &Outfile,string word, char space);

您的实施：

void putWord(ofstream &Outfile,string word, char c) { /* etc */ }

由于ostream和ofstream是不同的类型，因此不会编译。

C ++错误：未定义的符号

1 个答案: