问题:

解答:

<code>#include <iostream>

#include <vector>

#include <string>

#include <fstream>

#include <algorithm>

using namespace std;

const int LIMIT = 50;

void ShowStr(const string& str);

void GetStrs(ifstream& fin, vector<string>& v);

class Store

{

private:

string str;

ofstream* fout;

public:

Store(ofstream&out):fout(&out){ }

bool operator()(const string& str);

~Store(){ }

};

void ShowStr(const string& str)

{

cout << str << endl;

}

void GetStrs(ifstream& fin, vector<string>& v)

{

unsigned int len;

char* p;

while (fin.read((char*)&len, sizeof len))

{

p = new char[len];

fin.read(p,len);

v.push_back(p);

}

}

bool Store::operator()(const string& str)

{

unsigned int len = str.length();

if (fout->is_open())

{

fout->write((char*)&len, sizeof len);

fout->write(str.data(), len);

return true;

}

else

{

return false;

}

}

int main()

{

vector<string> vostr;

string temp;

cout << "Enter strings (empty line to quit):\n";

while (getline(cin, temp) && temp[0] != '\0')

vostr.push_back(temp);

cout << "Here is your input.\n";

for_each(vostr.begin(), vostr.end(),ShowStr);

ofstream fout("strings.txt", ios_base::in | ios_base::binary);

for_each(vostr.begin(), vostr.end(), Store(fout));

fout.close();

vector<string>vistr;

ifstream fin("strings.txt", ios_base::in | ios_base::binary);

if (!fin.is_open())

{

cerr << "Could not open the file for input.\n";

exit(EXIT_FAILURE);

}

GetStrs(fin, vistr);

cout << "\nHere are the strings read from the file:\n";

for_each(vistr.begin(), vistr.end(), ShowStr);

return 0;

}

拜了个拜!