1. Flow of Control
October 16, 2017

2. Constants
A declared constant is a variable whose value cannot be changed by the program.
A constant is declared using the modifier const:
const int WEEKDAYS = 5;
const double PI = ;
const string INITIALS = "BSC";
Standard practice is to write the name of a constant in all caps.

3. Arithmetic Shortcuts Some shortcuts besides x++ and x--:
x += 2; is the same as x = x + 2;
x -= 3; is the same as x = x - 3;
x *= 5; is the same as x = x * 5;
x /= 4; is the same as x = x / 4;
x %= 2; is the same as x = x % 2;

4. Switch Statements
A switch statement is similar to a series of if-else statements, but in some cases is a simpler implementation.
Every switch statement can be converted to an if-else statement, but not every if-else statement can be converted to a switch statement.
A switch statement is declared with the syntax switch (variable), where variable is the name of a variable, followed by curly braces.
Do not put a semicolon after switch (variable)!
The different possibilities (branches) are denoted using case.

5. break Statements The break statement can also be used to exit a loop.
For instance, a break statement can end a loop if improper input is detected.
Consider a program that asks the user to enter 10 negative numbers.
A break statement can be used to end the loop if the user enters zero or a positive number.

6. break Statements
int number, sum = 0, count = 1;
while(count <= 10) {
cin >> number;
if(number >= 0)
cout << "ERROR! Zero or positive number entered.\n";
break; }
The break; statement above terminates the loop if a nonnegative number is entered.

7. Sentinel Values
One way to allow the user to end a loop is through the use of a sentinel value.
This refers to a value added at the end of a list that is distinct from the other possible values in the list.

8. Sentinel Values
int number, sum = 0; cout << "Please enter a list of nonnegative integers.\n" << "Place a negative integer after the list.\n"; cin >> number; while(number >= 0) { sum = sum + number; }