zoukankan      html  css  js  c++  java
  • istream_iterator, ostream_iterator,copy以及文件序列化

    #include <iostream>
    #include <fstream>
    #include <algorithm>
    #include <cassert>
    #include <numeric>
    #include <string>
    using namespace std;

    int main()
    {
     vector<int> vec_int;
     for (int i=0; i<10; i++)
      vec_int.push_back(i);
     partial_sum(vec_int.begin(), vec_int.end(), vec_int.begin());
     vector<double> vec_double;
     for (int i=0; i<10; i++)
      vec_double.push_back(2.11);
     partial_sum(vec_double.begin(), vec_double.end(), vec_double.begin());
     vector<string> vec_str;
     for (int i=0; i<10; i++)
      vec_str.push_back("hkx");
     partial_sum(vec_str.begin(), vec_str.end(), vec_str.begin());
     //
     ostream_iterator<int> out(cout, ";");
     copy(vec_int.begin(), vec_int.end(), out);
     ostream_iterator<double> out1(cout, ";");
     copy(vec_double.begin(), vec_double.end(), out1);
     ostream_iterator<string> out2(cout, ";");
     copy(vec_str.begin(), vec_str.end(), out2);
     //

     ofstream ofs;
     ofs.open("hkx.dat");
     assert(ofs!= 0);
     ostream_iterator<int> os(ofs, ";");
     copy(vec_int.begin(), vec_int.end(), os);
     ostream_iterator<double> os1(ofs, ";");
     copy(vec_double.begin(), vec_double.end(), os1);
     ostream_iterator<string> os2(ofs, ";");
     copy(vec_str.begin(), vec_str.end(), os2);
     ofs.close(); //必须close,否则下面的ofstream中读取不到数据
     //

     ifstream ifs;
     ifs.open("hkx.dat");
     assert(ifs != NULL);
     vec_int.clear();
     vec_double.clear();
     vec_str.clear();

     copy(istream_iterator<int>(ifs), istream_iterator<int>(), back_inserter(vec_int));
     int ttm = vec_int.size();
     copy(vec_int.begin(), vec_int.end(), ostream_iterator<int>(cout, " "));

     ifs.clear();
     ifs.ignore(10, ';');
     copy(istream_iterator<double>(ifs), istream_iterator<double>(), back_inserter(vec_double));
     copy(vec_double.begin(), vec_double.end(), ostream_iterator<double>(cout, " "));

     ifs.clear();
     ifs.ignore(10, ';');
     copy(istream_iterator<string>(ifs), istream_iterator<string>(), back_inserter(vec_str));
     copy(vec_str.begin(), vec_str.end(), ostream_iterator<string>(cout, " "));

     return 0;
    }

  • 相关阅读:
    Random 种子问题
    Matrix issue
    Two sum.
    Best Time to Buy and Sell Stock
    Maximum difference between two elements
    二分查找法的实现和应用汇总
    Why you want to be restrictive with shrink of database files [From karaszi]
    Palindrome
    NetBeans vs Eclipse 之性能参数对比 [java060515]
    国内各大互联网公司相关技术站点不完全收录[转]
  • 原文地址:https://www.cnblogs.com/kex1n/p/2286432.html
Copyright © 2011-2022 走看看