1. Objective: Students will be able to: Declare and use variables Input integers

2. Variables Hold data Can be numbers, letters, words Place in main memory that holds the data Has a name that is assigned by the programmer

3. Example int alice; Type: int integer (whole number) alice: name of variable Variable is declared. ;

4. program to input an integer and have it print out (echo) #include using namespace std; int main (void) { int alice; cin >>alice; cout<< “There is an echo “; cout << alice; cin.get(); return0; }

5. Variable Names Can consist of numbers, letters, and underlines Can be as long as you like Provided that: It starts with a letter It is unique for that program somewhere in the first 32 characters Doug and doug are different Can’t be a keyword

6. Examples of variable names count Sum Salary, Next_character total reply

7. Type in and run the cin program. Make sure to type a number in when you run the program What were the results:

8. Assignment One way to assign a value to a variable is to input a number from the keyboard like we just did in the last program. Another way is to use an assignment statement: int alice, bill;declares variables cin>>aliceinput number for alice bill = alice;makes bill equal to alice cout<< bill;prints out number inputted

9. Self Test: What do these lines of code do? int Alice, Tom; cin >> Alice >> Tom; Alice = Tom; Tom = Alice; cout << Alice << Tom;

10. Answer goes here!

11. Self Test: What do these lines of code do? int Alice, Tom, Save; cin >> Alice >>Tom; Save = Alice; Alice = Tom; Tom = Save: cout<< Alice << Tom;

12. Answer goes here!