Convert the following Infix expression to its equivalent Postfix expression, showing the stack contents for each step of conversion.
P + ( Q - R ) * S / T

Write a function in C++ to read the content of a text file “DELHI.TXT” and display all those lines on the screen, which are either starting with ‘D’ or starting with ‘M’.

Write a function in C++ to search for the details (Phoneno and Calls) of those Phones, which have more than 800 calls from a binary file “phones.dat”. Assuming that this binary file contains records/objects of class Phone, which is defined below.

class Phone
{
	char Phoneno[10]; int Calls; 
public:
	void Get( ) 
	{ 
		gets(Phoneno); cin>>Calls; 
	}
	void Billing( )
	{
		cout<<Phoneno<<'#'<<Calls<<endl;
	}
	int GetCalls( )
	{
		return Calls;
	}
};