Error while using cin.get
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Thread: Error while using cin.get

  1. #1
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    Error while using cin.get

    Hi, Line 76: cin.get(g.handicap+count);
    Pre compile error dot in between cin and get. no instance of overload function ...


    Code:
    // golf.h -- for pe-9.cpp
    const int Len = 40;
    struct golf
    {
    	char fullname[Len];
    	int handicap;
    };
    
    //non-interactive version:
    //  function sets golf structure to provided name, handicap
    //  using vlues passed as arguments to the function
    void setgolf(golf & g, const char * name, int hc);
    
    // interactive version:
    // function name and handicap from user
    // and sets the members of g to the values entered
    // returns 1 if name is entered, 0 if name is empty string
    int setgolf(golf & g);
    
    // function resets handicap to new value
    void handicap(golf & g, int hc);
    
    // function displays contents of golf structure
    void showgolf(const golf & g);
    
    // chapEx9-1
    
    #include <iostream>
    #include "golf.h"
    using namespace std;
    
    int main()
    {
       golf ann;
    	setgolf(ann, "Ann Birdfree", 24);
    	showgolf(ann);
    	cout << "Enter how many golfers name and handicap do you want to enter: ";
    	int ngolfers;
    	cin >> ngolfers;
    	while (cin.get() != '\n')
    		continue;
    
    	golf * ptr_golf = new golf[ngolfers];
    
    	//int entered = getinfo
    	int rint = 1;
    	while (rint == 1)
    		rint = setgolf(ptr_golf);
    	showgolf(ann);
    }
    
    
    // golf.cpp load and show golf struc
    #include<iostream>
    #include "golf.h"
    
    using namespace std;
    
    void setgolf(golf & g, const char * name, int hc)
    {
    	strcpy_s(g.fullname, name);
    	g.handicap = hc;
    	// strlen(name)
    }
    
    int setgolf(golf & g)
    {
    	
    	static int count = 1;
    	static int pos = 0;
    
    	char fname[40];
    	cout << "Enter golfers name: ";
    	cin.getline(g.fullname+count, 40, '\n');
    	cout << "Enter golfers handicap: ";
    	cin.get(g.handicap+count);
    	cin.get();
    	
    	++count;
    
    	if (strlen(g.fullname) == 0)
    		return 0;
    	else
    	return 1;
    }
    
    
    void showgolf(const golf & g)
    {
    	cout << "\nFull name: " << g.fullname << "\n";
    	cout << "Handicap: " << g.handicap << "\n";
    }

  2. #2
    VictorN's Avatar
    VictorN is offline Super Moderator Power Poster
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    Re: Error while using cin.get

    Quote Originally Posted by FenixRising View Post
    Hi, Line 76: cin.get(g.handicap+count);
    Pre compile error dot in between cin and get. no instance of overload function ...


    Code:
    	cin.get(g.handicap+count);
    And what are you going to achieve with this line?
    Victor Nijegorodov

  3. #3
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    Posts
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    Re: Error while using cin.get

    I am trying to enter into the member handicap of the stuct golf of the handicap of the golfer entered. It is an integer.

  4. #4
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    Location
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    Posts
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    Re: Error while using cin.get

    cin.get reads a single character (!) from the input to a receiving buffer (!!). In the light of this g.handicap+count makes no sense, as this is not a buffer, and even if it were the one, you won't need the input character code to be put to your variable.
    Best regards,
    Igor

  5. #5
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    Location
    England
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    Re: Error while using cin.get

    Code:
    int setgolf(golf& g);
    This function declaration for setgolf takes one argument as a reference to a type called golf. However, when you call this function

    Code:
    rint = setgolf(ptr_golf);
    you are passing a pointer to an array of golf types.

    Either you need to have an additional function overload which takes as an argument a pointer to an array of golf, or the current one needs its argument changed.

    Code:
    char fname[40];
    	cout << "Enter golfers name: ";
    	cin.getline(g.fullname+count, 40, '\n');
    	cout << "Enter golfers handicap: ";
    	cin.get(g.handicap+count);
    I suspect that here you are trying to set the details of an individual element of the array pointed to by ptr_golf. However, this is not how it's done in c++. Arrays start at 0 and not 1 and are accessed either as

    Code:
    ptr_golf[count].handicap
    or
    Code:
    (ptr_golf + count)->handicap
    If g is a reference to a particular element of the ptr_golf array then the access would be

    Code:
    g.handicap
    The way you are trying to access
    Code:
    cin.get(g.handicap + count);
    is not valid c++

    Also the code

    Code:
    if (strlen(g.fullname) == 0)
    		return 0;
    	else
    		return 1;
    can be shorted to

    Code:
    return *(g.fullname) != 0;
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

  6. #6
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    Re: Error while using cin.get

    Can you give me some direction to accomplish what I want to do?

  7. #7
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    Re: Error while using cin.get

    What book are you using as you make reference to chap 9? If I was writing this program, I would be using a class with class functions to set/get golfers details.
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

  8. #8
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    Re: Error while using cin.get

    A simple example of doing this using a class could be

    Code:
    #include <iostream>
    #include <string>
    #include <map>
    using namespace std;
    
    typedef map<string, int> mapsi;
    typedef mapsi::iterator miter;
    typedef mapsi::const_iterator mciter;
    typedef pair<string, int> pairsi;
    
    class golfers {
    private:
    	mapsi details;
    
    public:
    	bool setperson(const string& name, int hc);
    	bool setperson();
    
    	bool set_hc(const string& name, int hc);
    	int get_hc(const string& name);
    
    	void  show_golfers();
    };
    
    bool golfers::setperson(const string& name, int hc)
    {
    	if (details.find(name) == details.end()) {
    		details.insert(pairsi(name, hc));
    		return true;
    	}
    
    	cout << "'" << name << "' already exists!" << endl;
    	return false;
    }
    
    bool golfers::setperson()
    {
    string name;
    
    int hc;
    
    	do {
    		cout << "full name: ";
    		getline(cin, name);
    		if (name.length() == 0) {
    			//cout << "no name entered!" << endl;
    			return false;
    		}
    
    		//Note no checking for invalid handicap input
    		cout << "handicap: ";
    		cin >> hc;
    		cin.ignore(100, '\n');
    	} while (setperson(name, hc) == false);
    
    	return true;
    }
    
    bool golfers::set_hc(const string& name, int hc)
    {
    miter dit;
    
    	if ((dit = details.find(name)) != details.end()) {
    		dit->second = hc;
    		return true;
    	}
    
    	cout << "'" << name << "' not found!" << endl;
    	return false;
    }
    
    int golfers::get_hc(const string& name)
    {
    miter dit;
    
    	return (dit = details.find(name)) != details.end() ? dit->second : 0;
    }
    
    void golfers::show_golfers()
    {
    mciter dcit;
    
    	for (mciter dcit = details.begin(); dcit != details.end(); ++dcit)
    		cout << dcit->first << "  " << dcit->second << endl;
    }
    
    int main()
    {
    golfers players;
    
    	players.setperson("Ann Birdfree", 24);
    	players.show_golfers();
    
    	while (players.setperson() == true);
    
    	players.show_golfers();
    }
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

  9. #9
    Join Date
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    Posts
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    Re: Error while using cin.get

    Hi,
    I'm using C++ Primer Plus. Classes are in the next chapter with objects.
    I am digesting what you have told me. I'll get back to you.

  10. #10
    Join Date
    Apr 2013
    Posts
    42

    Re: Error while using cin.get

    I have changed my program. I had some incorrect code left in the program. The program works as it has been written. But, the problem I am having now is how to enter multiple golf struct records using a loop with functions. I understand what your saying , but it was based on a incorrect premise.


    [CODE]
    // golf.h -- for pe-9.cpp
    const int Len = 40;
    struct golf
    {
    char fullname[Len];
    int handicap;
    };

    //non-interactive version:
    // function sets golf structure to provided name, handicap
    // using vlues passed as arguments to the function
    void setgolf(golf & g, const char * name, int hc);

    // interactive version:
    // function name and handicap from user
    // and sets the members of g to the values entered
    // returns 1 if name is entered, 0 if name is empty string
    int setgolf(golf & g);

    // function resets handicap to new value
    void handicap(golf & g, int hc);

    // function displays contents of golf structure
    void showgolf(const golf & g);

    // chapEx9-1

    #include <iostream>
    #include "golf.h"
    using namespace std;

    int main()
    {
    golf ann;
    setgolf(ann, "Ann Birdfree", 24);
    showgolf(ann);
    cout << "Enter how many golfers name and handicap do you want to enter: ";
    int ngolfers;
    cin >> ngolfers;
    while (cin.get() != '\n')
    continue;

    golf * ptr_golf = new golf[ngolfers];

    //int entered = getinfo
    int rint = 1;
    while (rint == 1)
    rint = setgolf(ann);
    showgolf(ann);
    }

    // golf.cpp load and show golf struc
    #include<iostream>
    #include "golf.h"

    using namespace std;

    void setgolf(golf & g, const char * name, int hc)
    {
    strcpy_s(g.fullname, name);
    g.handicap = hc;
    // strlen(name)
    }

    int setgolf(golf & g)
    {

    static int count = 1;
    static int pos = 0;

    cout << "Enter golfers name: ";
    cin >> g.fullname;
    cout << "Enter golfers handicap: ";
    cin >> g.handicap;

    ++count;

    /*if (strlen(g.fullname) == 0)
    return 0;
    else
    return 1;
    */
    return 0;
    }


    void showgolf(const golf & g)
    {
    cout << "\nFull name: " << g.fullname << "\n";
    cout << "Handicap: " << g.handicap << "\n";
    }

    [CODE]

  11. #11
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    Re: Error while using cin.get

    Doing it using your design, one possible way would be

    Code:
    #include <iostream>
    #include <cstring>
    using namespace std;
    
    const int Len = 40;
    
    struct golf
    {
    	char fullname[Len];
    	int handicap;
    };
    
    //non-interactive version:
    // function sets golf structure to provided name, handicap
    // using vlues passed as arguments to the function
    void setgolf(golf & g, const char * name, int hc);
    
    // interactive version:
    // function name and handicap from user
    // and sets the members of g to the values entered
    // returns 1 if name is entered, 0 if name is empty string
    int setgolf(golf & g);
    
    // function resets handicap to new value
    //void handicap(golf & g, int hc);
    
    // function displays contents of golf structure
    void showgolf(const golf & g);
    
    void iflush()
    {
    	while (cin.get() != '\n');
    }
    
    int main()
    {
    golf ann;
    
    	setgolf(ann, "Ann Birdfree", 24);
    	showgolf(ann);
    
    	cout << "Enter how many golfers name and handicap do you want to enter: ";
    
    int ngolfers;
    
    	cin >> ngolfers;
    	iflush();
    
    golf * ptr_golf = new golf[ngolfers];
    
    int count = 0;
    int got = 1;
    
    	while (count < ngolfers && got)
    		count += (got = setgolf(ptr_golf[count]));
    
    	for (int c = 0; c < count; c++) 
    		showgolf(ptr_golf[c]);
    
    	delete [] ptr_golf;
    	return 0;
    }
    
    // golf.cpp load and show golf struc
    
    void setgolf(golf & g, const char * name, int hc)
    {
    	memset(g.fullname, 0, Len);
    	strncpy(g.fullname, name, Len - 1);
    	g.handicap = hc;
    }
    
    int setgolf(golf & g)
    {
    	cout << "Enter golfers name: ";
    	cin.getline(g.fullname, Len);
    	if (*(g.fullname) == 0)
    		return 0;
    
    	cout << "Enter golfers handicap: ";
    	cin >> g.handicap;
    	iflush();
    
    	return 1;
    }
    
    
    void showgolf(const golf & g)
    {
    	cout << "\nFull name: " << g.fullname << "\n";
    	cout << "Handicap: " << g.handicap << "\n";
    }
    Last edited by 2kaud; September 16th, 2013 at 09:46 AM.
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

  12. #12
    Join Date
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    Posts
    27,427

    Re: Error while using cin.get

    Quote Originally Posted by FenixRising View Post
    I have changed my program. I had some incorrect code left in the program. The program works as it has been written.
    First, use code tags correctly. The code you posted is almost unreadable due to using improper code tags.

    Second:
    Code:
    const int Len = 40;
    struct golf
    {
        char fullname[Len];
        int handicap;
    };
    //...
    cout << "Enter golfers name: ";
    cin >> g.fullname;
    What if the name is greater than 40 characters (including the terminating NULL)? You now have a memory overwrite error, possibly causing your program to crash.

    On a more general note, why are you resorting to 'C' style character handling? Since you're using C++, why not use a string class such as std::string?

    Next, there is a memory leak in your code:
    Code:
    golf * ptr_golf = new golf[ngolfers];
    There is no call to deallocate the memory (where is delete[] ptr_golf?)

    Regards,

    Paul McKenzie

  13. #13
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    Re: Error while using cin.get

    See the code in my post #11 which takes into account the 2 code points raised by Paul.
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

  14. #14
    Join Date
    Apr 2013
    Posts
    42

    Re: Error while using cin.get

    Hi, sorry that i took so long to respond.

    I have changed my code and now have a pre-compile error in this line: void setgolf(golf & g, const char * name, int hc)

    setgolf is the first error flagged.

    Plus, I see there is a function that is not defined in the program memset; memset(g.fullname, 0, Len); in the same function. I am not familiar with it

  15. #15
    VictorN's Avatar
    VictorN is offline Super Moderator Power Poster
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    Re: Error while using cin.get

    1.
    Quote Originally Posted by FenixRising View Post
    I have changed my code and now have a pre-compile error in this line: void setgolf(golf & g, const char * name, int hc)

    setgolf is the first error flagged.
    And what is the exact error message and error code?
    2.
    Quote Originally Posted by FenixRising View Post
    Plus, I see there is a function that is not defined in the program memset; memset(g.fullname, 0, Len);
    Well, don't you know how to search with Google? How to use MSDN?
    http://www.cplusplus.com/reference/cstring/memset/
    http://msdn.microsoft.com/en-us/library/1fdeehz6.aspx

    3. Please, use Code tags!
    Victor Nijegorodov

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