C++课程作业

 #include <fstream>

    
 #include <iostream>
    
 #include <string>
    
  
    
 int main(int argc, const char* argv[]) {
    
     // open oldmast.dat for input
    
     std::ifstream inOldMaster("oldmast.dat", std::ios::in);
    
  
    
     if (!inOldMaster) {
    
     std::cerr << "oldmast.dat could not be opened" << std::endl;
    
     return 0;
    
     }
    
     // open transaction file for input
    
     std::ifstream inTransaction("trans.dat", std::ios::in);
    
  
    
     if (!inTransaction) {
    
     std::cerr << "trans.dat could not