illegal structure operation

[ketanharsoda]

#include<iostream.h>
#include<conio.h>
class date
{
	int dd,yy,day,*incr;
	char *mon; //first latter

	public:
	void setptr(date *m);
	void getdata();
	void putdata();
};
void date::setptr(date *m)
{
	char *month[]={"jan","feb","mar","apr","may","jun","jul","aug","sep","oct","nov","dec"};
	for(int i=0;i<=11;i++)
	{
	      if(*m==*month[i])
	      {
		*incr=*month[i];
		cout<<*incr;
		break;
	      }
	}
}
void date::getdata()
{
	date s;
	cout<<"enter in dd,mon,yy foramt";
	cout<<"\nenter day:";
	cin>>dd;
	cout<<"enter month";
	cin>>mon;
	cout<<"enter year";
	cin>>yy;
	cout<<"enter no.of days you want to enter:";
	cin>>day;
	s.setptr(mon);
}
void date::putdata()
{
	cout<<endl;
	cout<<"DATE:"<<dd<<":"<<mon<<":"<<yy;
}

void main()
{
	clrscr();
	date d1;
	d1.getdata();
	getch();
}

[weaknessforcats]

This code:

void date::setptr(date *m)
{
	char *month[]={"jan","feb","mar","apr","may","jun","jul","aug","sep","oct","nov","dec"};
	for(int i=0;i<=11;i++)
	{
	      if(*m==*month[i])
	      {
		*incr=*month[i];
		cout<<*incr;
		break;
	      }
	}
}

has several problems.
1) The function attempts to take an address from a local variable month[] and use it outside the function.

2) Coding (*m==*month[i])requires and operator==(char *) member function and there is no such function.

3) This member function is used in date::getdata by passing in a char* when the function requires a date*.

4) The code s.setptr(mon); inside date::getdata() uses a local date variable which is then destroyed when the function completes. This may mean you need to learn how to use the this operator.

5) main() returns an int not a void.

6) iostream.h is pre-1998 C++. I would try to get something newer. iostream.h is not ANSI standard and has some bugs in it.