输出一直是0
#include <iostream>
#include <fstream>
#include <cstdlib>
#include <string>
using namespace std;
int main()
{
fstream fp("D:\\Application\\Visual Studio 2013\\test");
if (!fp.is_open())cout << "0";
char c = 'm';
fp.put(c);
fp.close();
return 0;
}