Algorithms

What is an algorithm?

• A set of steps to accomplish something.

• A set of variables.

• A set of known data.

• A set of anti virus code.

What is Pseudocode?

• Sketch out the logical steps of a process before using a programming language.

• Python sublanguage.

• C++ sublanguage.

• Sketch out the logical steps of a process before compiling a code.

Get egg carton from the fridge.

______________

Break egg into bowl.

Get flour bag from pantry.

Take flour out of bag.

Pour flour into bowl.

What is missing from this pseudocode?

• Take egg out of carton.

• Put egg in flour bag.

• Put flour back in pantry.

• Put egg carton back in fridge.

Describes a test condition.

List some instructions that should run if the test succeeds.

• conditional instructions

• unconditional instructions

• variable instructions

• input instructions

Which is a conditional instruction?

• if it is dark outside:

  turn on the lights

• x= x - 1

• x= x + 1

• input("What is your favorite color")

A “while” instruction continues running until its test ______.

• fails

• repeats

• Decrements to zero.

• Increments by the value of i.

Removing which statement will make this an infinite loop?

• set countdown to countdown - 1

• print a black and white page

• while countdown > 0:

• set countdown to 3

If there are 4 people in the room, how many times does line 3 execute?

Let N=0

For each pair of people in the room

Set N= N+2

• 0

• 1

• 2

• 4

If there are 13 people in the room, how many times does line 5 execute?

Let N=0

For each pair of people in the room

Set N= N+2

If 1 person remains then

Set N= N+1

• 0

• 1

• 13

• 6

If there are 50 people in the room, which line never executes? Why?

Let N=0

For each pair of people in the room

Set N= N+2

If 1 person remains then

Set N= N+1