Зміст курсу

Learn Python from Scratch

1. The basics

Hello, World!Hello, me!Variables Comments Indentation Numbers and strings

2. Arithmetic operations

Addition Multiplication and power Division and whole part division

3. Common data types

Data types Numbers float and int Storing text Strings slicing Concatenation

4. Conditional statements

Boolean data type Combining conditions Simple if/else expressions (1/2)Simple if/else expressions (2/2)If/else expressions with multiple conditions (1/2)If/else expressions with multiple conditions (2/2)

5. Other data types

Lists (1/3)Lists (2/3)Lists (3/3)Tuples (1/3)Tuples (2/3)Tuples (3/3)Dictionaries (1/2)Dictionaries (2/2)

6. Loops

while loop (1/2)while loop (2/2)for loop (1/5)for loop (2/5)for loop (3/5)for loop (4/5)for loop (5/5)

7. Functions

Built-in functions Writing your own functions (1/5)Writing your own functions (2/5)Writing your own functions (3/5)Writing your own functions (4/5)Writing your own functions (5/5)lambda functions

Simple if/else expressions (1/2)

Okay, now we are familiar with conditional operators and know how to deal with them. It means now we can divide our code into pieces depend on the condition. In Python, its implemented like the follows:


              1234
            
if condition:
   do if true
else
   do if not true

For example, remember our primitive example about deciding whether to go walk or not. We can write it in Python syntax like that:


              1234
            
if (weather is good and (day is Sunday or day is Saturday)):
   go walk
else:
   stay home :(

Consider some examples: imagine you have some string and want to check if it's wide. Let's call string wide if it has more than 20 symbols.


              1234567891011121314151617
            
# assign some variable
test = "small string"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")
    
# check on different string
test = "This string is very-very and very large"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")

Please note, that code blocks written below if, else statements need to be indented on the same level (2 spaces, 3, 4, ...). The main condition - the equal number.

Assume you own a small grocery and spend 2000 dollars every day. Obviously, if your revenue per day is less than 2000, then you suffer losses, otherwise - nothing bad. Let's try to write if/else statement for that.

Завдання

Write conditional statement checking if variable revenue is less than 2000 (in that case print message "We suffer losses!", otherwise - print "Everything is ok!"). Do not change value of revenue.

Завдання

Перейдіть на комп'ютер для реальної практикиПродовжуйте з того місця, де ви зупинились, використовуючи один з наведених нижче варіантів

Все було зрозуміло?

Секція 4. Розділ 3

Simple if/else expressions (1/2)


              1234
            
if condition:
   do if true
else
   do if not true

For example, remember our primitive example about deciding whether to go walk or not. We can write it in Python syntax like that:


              1234
            
if (weather is good and (day is Sunday or day is Saturday)):
   go walk
else:
   stay home :(

Consider some examples: imagine you have some string and want to check if it's wide. Let's call string wide if it has more than 20 symbols.


              1234567891011121314151617
            
# assign some variable
test = "small string"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")
    
# check on different string
test = "This string is very-very and very large"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")

Please note, that code blocks written below if, else statements need to be indented on the same level (2 spaces, 3, 4, ...). The main condition - the equal number.

Завдання

Все було зрозуміло?

Секція 4. Розділ 3

Simple if/else expressions (1/2)


              1234
            
if condition:
   do if true
else
   do if not true

For example, remember our primitive example about deciding whether to go walk or not. We can write it in Python syntax like that:


              1234
            
if (weather is good and (day is Sunday or day is Saturday)):
   go walk
else:
   stay home :(

Consider some examples: imagine you have some string and want to check if it's wide. Let's call string wide if it has more than 20 symbols.


              1234567891011121314151617
            
# assign some variable
test = "small string"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")
    
# check on different string
test = "This string is very-very and very large"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")

Please note, that code blocks written below if, else statements need to be indented on the same level (2 spaces, 3, 4, ...). The main condition - the equal number.

Завдання

Все було зрозуміло?


              1234
            
if condition:
   do if true
else
   do if not true

For example, remember our primitive example about deciding whether to go walk or not. We can write it in Python syntax like that:


              1234
            
if (weather is good and (day is Sunday or day is Saturday)):
   go walk
else:
   stay home :(

Consider some examples: imagine you have some string and want to check if it's wide. Let's call string wide if it has more than 20 symbols.


              1234567891011121314151617
            
# assign some variable
test = "small string"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")
    
# check on different string
test = "This string is very-very and very large"

# conditional statement
if(len(test) > 20):
    print("This string is wide!")
else:
    print("Nothing special")

Please note, that code blocks written below if, else statements need to be indented on the same level (2 spaces, 3, 4, ...). The main condition - the equal number.

Завдання

Секція 4. Розділ 3