【转】C++文件流の添加数字到指定文件中

#include<iostream>
#include<fstream>
using namespace std;

void main()
{
  int a;
  int c;
  ifstream in ("abc.txt");
  in>>a;
  in.close();
  in.clear();
  ofstream file("abc.txt", ios::out | ios::app);
  file<<5;  //输入一个数如5
  file.close();
  file.clear();
  in.open("abc.txt");

  in>>c;
  in.close();
  in.clear();
  cout<<a<<endl;
  cout<<c<<endl;
}

转载于:https://www.cnblogs.com/lzhitian/archive/2012/11/26/2789838.html