Console Input and Output

Input-Output Stream:
   a sequence of characters from an input device to the computer, or from the
   computer to an output device.

General form of the cin statement:  cin >> variable [ >> variable ] ...;
    The extraction operator (>>) skips all whitespace* characters, then
    extracts the next value corresponding to the variable's data type;
    whereas the insertion operator (>>) places data from memory into the output
    stream.  (* blank, tab, return code)
    
    Preprocessor directive required for cin and cout:  #include <iostream>
    
    Namespace statement for direct reference to cin & cout: using namespace std;

1.  Given a type double variable named gasPrice, code a cin statement to input 
    and extract a value for storing (sample input: 3.35).


2.  Suppose you drive some distance in whole miles and use a certain amount
    of gasoline (could have a fractional portion). Define variables for the 
    miles driven and for gasoline used. Then code a cin statement to input
    both milesDriven and gasUsed.
        

General form of the cout statement:
    cout << expression or manipulator [ << expression or manipulator ] ...;
   
3.  Code cout statements for use as prompts to input gasPrice, milesDriven and
    gasUsed prior to the cin statements for questions 1 and 2.


       
4.  Code cout statement(s) to print the string "MPG = " as a side label prior 
    to an expression of milesDriven divided by gasUsed. 
    

Input-Output and the string type:
   Preprocessor directive:   #include <string>
      may be needed when processing variables of the data type string
   
   Example: given an input stream containing Commerce Texas, for the statement:
      cin >> city;     
      
      only Commerce stored because extraction terminates when whitespace sensed.
      [note: a cout statement will print an entire string containing whitespace]

5.  Given that a string named state has been declared, code cin statement(s)
    to input and store Commerce as city and Texas as state.


General form of the getline function:  getline(istreamVar, strVar);
    This function reads until it reaches the end of the current line;
    Example:  getline(cin, city); 
    
    (With "Fort Worth" in the stream, both  words would be stored in city.)
    
General form of cin.get:  cin.get([varChar])
    This inputs the next character without skipping whitespace.

6.  Code a string variable named courseTitle, a prompt, then a getline() 
    statement to extract the words "Introduction to Computer Science" from the
    input stream to assign to courseTitle. "Echo" courseTitle.