STL: for_each-白红宇

STL: for_each

阅读量：2297 次

发布时间：2019-05-09

本文共 1345 字，大约阅读时间需要 4 分钟。

#include 
   
      #include 
    
       #include 
     
        #include 
      
         using namespace std;    class GenByTwo {      public:          GenByTwo (int _seed = 0):seed(_seed){}          int operator() () {return seed += 2;}        private:          int seed;  };    void operate(int &rhs)  {      cout << rhs << " ";      rhs += 1;  }  int main(int argc, char* argv[])  {      vector
       
         v(10);      generate(v.begin(), v.end(), GenByTwo(2));      for_each(v.begin(), v.end(), operate);        std::cout << std::endl;    //print      copy(v.begin(), v.end(), ostream_iterator
        
         (cout, " ")); return 0; }

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#include 
   
         // std::cin, std::cout#include 
    
          // std::istream_iterator#include 
     
      #include 
      #include 
       
        #include 
        
         #include 
         
          using namespace std;map
          
            m;void print( const pair
           
             &r){ cout << r.first << " " << r.second << endl;}void record( const string &s){ m[ s ] ++;}int main(){ double beginTime = clock(); fstream in("test.txt"); istream_iterator
            
              ii(in); istream_iterator
             
               eos; for_each(ii,eos,record); for_each( m.begin(), m.end(), print); double endTime = clock(); cout << " time: " << endTime - beginTime << " ms" << endl; return 0;}