Concepts and Terminology
A procedure for solving a problem in terms of the actions to execute and the order in which these actions execute.
Statement of the solution to a problem in English, without the syntax of a language. Pseudocode normally describes only executable statements. It is used to develop an algorithm.
|
Operator |
Example Expression |
Meaning |
|
+= |
c += 7 |
c = c + 7 |
|
-= |
c -= 4 |
c = c - 4 |
|
*= |
c *= 3 |
c = c*3 |
|
/= |
c /= 9 |
c = c/9 |
|
%= |
c %= 2 |
c = c % 2 |
Increment and Decrement Operators (we will focus on the ones in red - primarily the first one: ++)
|
Operator |
Name |
Example |
Meaning |
|
++ |
preincrement |
++a |
Increment a by 1, then use the new value of a in the expression in which a resides |
|
++ |
postincrement |
a++ |
Use the current value of a in the expression in which a resides, then increment by 1 |
|
- - |
predecrement |
- - b |
Decrement by 1, then use the new value of b in the expression in which b resides |
|
- - |
postdecrement |
b - - |
value of b in the expression in which b resides, then decrement by 1 |
Note: For non-integer increments or decrements, you cannot use ++ or --. In this case the longer version (a = a + 1.07, for example, is required.
if (this chapter), if else (this chapter), switch (chapter 5)
if:
if (a > b)
{
}
Checks the Boolean at the beginning - may not execute at all
If Boolean is true, the following statement executes
If Boolean is false, the following statement is skipped
if else:
if (a > b)
{
//code
}
else
{
//code
}
Boolean if checked at beginning, may not execute at all
Checks the Boolean following the if, same as above
However, if Boolean if false, the else statement is executed
switch: (covered later)
Selects from alternatives
Useful in situations where a large number of if statements would be required
while (this chapter), do while (chapter 5), for (chapter 5)
while:
while (a > b)
{
//code
//counter increment or decrement statement
}
Boolean is checked at beginning - may not execute at al
Executes as long as the Boolean is true
If Boolean is false, the statement is skipped
When Boolean becomes false, remaining statements are executed
Need a sentinel that is either incremented or decremented - otherwise get an infinite loop
do while:
do
{
//code
//counter increment or decrement statement
}
while (a > b)
Note that it always executes at least once
Boolean is checked at the end
for:
for (int a = 1; a <=10;a++)
{
}
Repeats for a specified number of times until termation condition is encountered
Not tested but may be on lab exercises
Used to change the data type of a variable for an operation
It does not change the original declaration for the data type of the variable
