Problem 1: Write a program to overload the postfix decrement operator for the class "demo" containing two data members as x and y.
Problem 2: Write a program to design a class named STUDENT with data members - Name, roll no, marks in physics, chemistry and maths, also create a member function to take input of all these details. Create another class named- SPORTS with data member smarks and make a member function to take input for the same. From these two classes create/inherit one class RESULT to calculate the final result that is the percentage of the student and display it on screen.
Problem 3: Write a program to save a string- "Welcome to the world of C++ programming" in a file and displays only vowels from this file on the screen.
Problem 4: Students of a school were attending a magic show. The magician needs a student volunteer for performing a trick. So, he asked one of the students to come on the stage. As the show was interesting so all the students were ready to participate in the show. To choose one volunteer, the magician asked the teacher to select one of the students. The teacher told the students that the tallest student should go on the stage.
Input: Enter the height of the students in integer. Output: Maximum height is displayed.
Constraints: Height cannot be negative and input should be taken dynamically.