Homework 3 - Functions and Strings

Name your files hw3_<problem>.cpp, such as hw3_1.cpp. Email all the cpp files to my Helios account.

1. (5 points) This purpose of this problem is to work with function overloading. You will write several versions of functions called find_min(), get_input() and print_min(). The functions are as follows:
   • The first version of print_min() will take an integer and print the message "The minimum is <value>.\n".
   • The second version of print_min() will take a double and print the message "The minimum is <value>.\n" with 4 decimal places of precision for <value>.
   • The first version of find_min() will return the minimum of two integer parameters.
   • The second version of find_min() will return the minimum of two double parameters.
   • The third version of find_min() will return the minimum of three integer parameters.
   • The first version of get_input() has two integer by-reference parameters. It will prompt the user for two integers and read them into the parameter variables.
   • The second version of get_input() has two double by-reference parameters. It will prompt the user for two double and read them into the parameter variables.
   • The third version of get_input() has three integer by-reference parameters. It will prompt the user for three integers and read them into the parameter variables.
   Use the following main function for this problem:

   int main()
   {
     int num1, num2, num3;
     double dnum1, dnum2;
   
     // Two integer version
     get_input(num1, num2);
     print_min(find_min(num1, num2));
   
     // Two double version
     get_input(dnum1, dnum2);
     print_min(find_min(dnum1, dnum2));
   
     // Three integer version
     get_input(num1, num2, num3);
     print_min(find_min(num1, num2, num3));
   
     return 0;
   }
   

2. (5 points) For this program, you will read in a name and ID number from the user and then format it when outputting it to the screen. Your program will have two functions:
   • get_input() will take a C-style string and a by-reference integer as parameters. It will prompt the user for the last name and read that in to the C-style string parameter. It will then prompt for the ID number, clear any non-digit characters off the input stream and then read the ID number in to the integer parameter.
     Note: You will be marked off if you do not clear the non-digit characters off the input stream before reading in the ID number. This guards against someone accidently entering the whole name instead of just the last name.
   • print_student() will have a C-style string and an integer parameter. It will print the name out in a 20 character wide column. The ID will be printed out in a 10 character wide column with 0 padding.
   In main, use a do-while loop that will call get_input() then print_student() and then ask if the user wishes to enter another student's information. After reading in the first character of the user's answer, clear the input stream. So if the user types 'yes', read 'y' into a character and then remove "es" from the input stream. If you neglect this step, the remaining characters will be read in as the last name in the next iteration of the loop and points will be deducted. Exit the do-while loop when the user enters 'n' or 'N'.

3. (10 points) Modify your simple menu program from Homework 2. The menu options will remain the same, but now each option will use a function calls instead of having all the option statements within the switch() statement. Additionally, if you did not use a do-while loop in Homework 2 for your menu, convert your menu over to use a do-while loop.

     Welcome to the CS221 Homework 3 Menu
     ====================================
     1.  Multiply two integers
     2.  Divide two integers
     3.  Check if a number is within the range 10-20
     4.  Find the minimum of a list of 3 numbers
   
     0.  Exit
     ====================================
     Enter selection:
   

   From within each case statement, there will be a void function that gets the input from the user using by-reference parameters and a second void function that takes the input as by-value parameters, does the task and prints the result to the screen. For example, the first menu item case statement would be:

     case 1:
       int a, b;
       get_input(a, b);
       do_multiply(a, b);
       break;
   

   You should have at least the following 7 void functions in your final code. More functions are fine if you wish to break each menu item task into subtasks.
   • 3 versions of get_input(). One version will have one by-reference integer, the second version will have two by-reference integers and the third will have three by-reference integers. Each will prompt the user for the required number of integers and read in to the by-reference parameters.
   • do_multiply(int a, int b) will multiply the integers and print the result to the screen.
   • do_division(int a, int b) will divide the integers and print the result to the screen.
   • do_check(int a) will check if the integer is in range. If it is in range, it will print that it is in range to the screen. Otherwise, it will print that it is not in range.
   • do_minimum(int a, int b, int c) will find the minimum and print it to the screen.