/in/call.cpp:12:9: error: unknown type name 'string'; did you mean 'std::string'?
        string callername;
        ^~~~~~
        std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:19:39: error: unknown type name 'string'; did you mean 'std::string'?
    void initialization(int timestamp,string callername, string status, int duration);
                                      ^~~~~~
                                      std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:19:58: error: unknown type name 'string'; did you mean 'std::string'?
    void initialization(int timestamp,string callername, string status, int duration);
                                                         ^~~~~~
                                                         std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:24:11: error: unknown type name 'string'; did you mean 'std::string'?
    const string getcallername();
          ^~~~~~
          std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:30:43: error: unknown type name 'string'; did you mean 'std::string'?
void caller::initialization(int timestamp,string callername, string status, int duration){
                                          ^~~~~~
                                          std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:30:62: error: unknown type name 'string'; did you mean 'std::string'?
void caller::initialization(int timestamp,string callername, string status, int duration){
                                                             ^~~~~~
                                                             std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:53:7: error: unknown type name 'string'; did you mean 'std::string'?
const string caller::getcallername(){
      ^~~~~~
      std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:67:5: error: unknown type name 'string'; did you mean 'std::string'?
    string nameofstatue[4]={"regular","silver","gold","platinum"};
    ^~~~~~
    std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:74:5: error: use of undeclared identifier 'cin'; did you mean 'std::cin'?
    cin >> calleramount;
    ^~~
    std::cin
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/iostream:60:18: note: 'std::cin' declared here
  extern istream cin;           /// Linked to standard input
                 ^
/in/call.cpp:80:24: error: unknown type name 'string'; did you mean 'std::string'?
        int timestamp; string callername; string status; int duration;
                       ^~~~~~
                       std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:80:43: error: unknown type name 'string'; did you mean 'std::string'?
        int timestamp; string callername; string status; int duration;
                                          ^~~~~~
                                          std::string
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/stringfwd.h:74:33: note: 'std::string' declared here
  typedef basic_string<char>    string;   
                                ^
/in/call.cpp:81:9: error: use of undeclared identifier 'cin'; did you mean 'std::cin'?
        cin >> timestamp >> callername >> status >> duration;
        ^~~
        std::cin
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/iostream:60:18: note: 'std::cin' declared here
  extern istream cin;           /// Linked to standard input
                 ^
/in/call.cpp:91:9: error: use of undeclared identifier 'cout'; did you mean 'std::cout'?
        cout << "Starting tick #" << currenttime << endl;
        ^~~~
        std::cout
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/iostream:61:18: note: 'std::cout' declared here
  extern ostream cout;          /// Linked to standard output
                 ^
/in/call.cpp:91:53: error: use of undeclared identifier 'endl'; did you mean 'std::endl'?
        cout << "Starting tick #" << currenttime << endl;
                                                    ^~~~
                                                    std::endl
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/ostream:590:5: note: 'std::endl' declared here
    endl(basic_ostream<_CharT, _Traits>& __os)
    ^
/in/call.cpp:95:17: error: use of undeclared identifier 'cout'; did you mean 'std::cout'?
                cout << "Call from "<< temp_printcall->getcallername() <<" a " << nameofstatue[temp_printcall->getstatus()]<<" member" << endl;
                ^~~~
                std::cout
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/iostream:61:18: note: 'std::cout' declared here
  extern ostream cout;          /// Linked to standard output
                 ^
/in/call.cpp:95:139: error: use of undeclared identifier 'endl'; did you mean 'std::endl'?
                cout << "Call from "<< temp_printcall->getcallername() <<" a " << nameofstatue[temp_printcall->getstatus()]<<" member" << endl;
                                                                                                                                          ^~~~
                                                                                                                                          std::endl
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/ostream:590:5: note: 'std::endl' declared here
    endl(basic_ostream<_CharT, _Traits>& __os)
    ^
/in/call.cpp:120:17: error: use of undeclared identifier 'cout'; did you mean 'std::cout'?
                cout << "Answering call from " << try_deal->getcallername() << endl;
                ^~~~
                std::cout
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/iostream:61:18: note: 'std::cout' declared here
  extern ostream cout;          /// Linked to standard output
                 ^
/in/call.cpp:120:80: error: use of undeclared identifier 'endl'; did you mean 'std::endl'?
                cout << "Answering call from " << try_deal->getcallername() << endl;
                                                                               ^~~~
                                                                               std::endl
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/ostream:590:5: note: 'std::endl' declared here
    endl(basic_ostream<_CharT, _Traits>& __os)
    ^
/in/call.cpp:130:5: error: use of undeclared identifier 'cout'; did you mean 'std::cout'?
    cout << "Starting tick #" << currenttime << endl;
    ^~~~
    std::cout
/usr/bin/../lib/gcc/x86_64-linux-gnu/7.4.0/../../../../include/c++/7.4.0/iostream:61:18: note: 'std::cout' declared here
  extern ostream cout;          /// Linked to standard output
                 ^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
20 errors generated.
/in/Compile/Makefile:39: recipe for target 'buildCall' failed
make: *** [buildCall] Error 1