CS50x 2025 - Lecture 0 - Scratch
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Computer Science. Computational Thinking. Problem Solving: Inputs, Outputs. Representation: Unary, Binary, Decimal, ASCII, Unicode, RGB. Abstraction. Algorithms. Running Times. Pseudocode. Scratch: Functions, Arguments, Return Values; Variables; Boolean Expressions, Conditionals; Loops; Events; Threads.
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TABLE OF CONTENTS
00:00:00 - Introduction
00:01:15 - This is CS50
00:08:35 - Computer Science
00:09:44 - Unary
00:11:28 - Binary
00:23:58 - ASCII
00:33:42 - Unicode
00:38:45 - Color
00:42:27 - Representation
00:47:20 - Algorithms
00:57:34 - Pseudocode
01:03:32 - Artificial Intelligence
01:09:21 - Scratch
01:16:15 - Hello, World
01:19:00 - Hello, You
01:27:02 - Meow
01:32:21 - Abstractions
01:37:23 - Conditionals
01:41:14 - Oscartime
01:49:52 - Ivy’s Hardest Game
***
This is CS50, Harvard University's introduction to the intellectual enterprises of computer science and the art of programming.
***
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Hello, World: Hadi Partovi
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Week 3, continued
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Chapters (20)
Introduction
1:15
This is CS50
8:35
Computer Science
9:44
Unary
11:28
Binary
23:58
ASCII
33:42
Unicode
38:45
Color
42:27
Representation
47:20
Algorithms
57:34
Pseudocode
1:03:32
Artificial Intelligence
1:09:21
Scratch
1:16:15
Hello, World
1:19:00
Hello, You
1:27:02
Meow
1:32:21
Abstractions
1:37:23
Conditionals
1:41:14
Oscartime
1:49:52
Ivy’s Hardest Game
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Tutor Explanation
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