Write a function that evaluates an expression in RPN that is given as a string.

Define a structure of type hms containing three integer members, called hour, minute and second, respectively. Then define a union containing two members, each a structure of type hms. Call the union members local and home, respectively. Declare a pointer variable called time that points to this union.

Explain how will you read a three-dimensional array using for loops.

How would you differentiate between the terms pointer to an array and array of pointers? Give proper examples.

Explain the use of the functions getchar(), putchar(), gets() and puts() functions, with a suitable program

What do you understand by file organisation? Explain the methods of file organisation.

Write a C program which reads a line of text from keyboard, and writes the line to a file with lower case letters converted to upper case and vice-versa