APT Quiz 1 Exam 1 is Sept 24, next Thursday APT Quiz 1 is 9/25-9/28 - - PowerPoint PPT Presentation

Compsci 101 Turtle, Bagels, Loop Tracing, Files Live Lecture

9/15/2020 Compsci 101, Fall 2020 1

Susan Rodger September 15, 2020

Announcements

• APT-2 due tonight!
• Remember you get 24-hour grace period, can’t

turn in after that!

• APT-3 out today – due 9/22
• Assignment 2 Turtles out – due 9/29
• Lab 4 Friday – has prelab to do before lab!

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Exam 1 Studying

• Exam 1 is Sept 24, next Thursday
• Covers topics through this week
• Not while loops, not files
• How to study
• Write code on paper or type code in a plain text file
• Redo code you have already done, we did class
• Try things in Python Tutor, in Python Console
• Review all notes
• Old tests on Resources tab
• Spring 18 on, is Python 3, Before that Python 2
• Try timing yourself on old exams?
• CS101 Reviewer APP – use in prelab for Lab 4

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APT Quiz 1

• APT Quiz 1 is 9/25-9/28 (no lab on 9/25)
• Open around 8am 9/25
• Pick your start time,
• Once you start, You have 2.5 hours
• If you get accommodations, you get those
• 3 APTs to solve
• Will put up problems from an old APT Quiz so you

can practice

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WOTO-1 – Turtles Simple http://bit.ly/101f20-0915-1

• If you are done early, revise and collaborate on

your notes!

• In your groups:
• Come to a consensus

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WOTO-2: Let’s draw a triangle! http://bit.ly/101f20-0915-2

• Equilateral triangle
• Corner degrees: 60
• Side length: 100

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Bagels (Accumulation)

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This Photo by Unknown Author is licensed under CC BY-NC-ND

APT Bagels

• How figure out how many bagels needed?
• 7-steps!

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Examples

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Step 1 and 2

• Step 1: Solve an instance (think)
• orders = [11, 3, 24, 17]

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WOTO-3 Step 3: Generalize http://bit.ly/101f20-0915-3

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Donald Knuth

• Until recently …
• Was "The Donald"
• Turing, Hopper, more …
• Author of many works

Art of Computer Programming Mad Magazine when 19 (author of TeX) “I can’t go to a restaurant and order food because I keep looking at the fonts on the menu.”

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Code-Tracing a Loop

• 1. Find the changing variables/expressions
• 2. Create table, columns are variables/expressions
• 1. First column is loop variable
• 2. Add columns to help track everything else
• 3. Each row is an iteration of the loop
• 1. Before execute code block, copy down each

variable’s value

• 2. Execute code block, update a value in the row

as it changes

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WOTO Loop Tracing http://bit.ly/101f20-0915-4

• Remember the steps (1) Find the changing

variable/expressions, (2) Create the table with these as the column, and (3) Each row is an iteration of the loop

• In your groups:
• Come to a consensus

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