Вивчайте Concatenation, Repetition, and Basic Formatting

Свайпніть щоб показати меню

You often need to build messages from pieces (names, numbers, results). Python gives you three core tools: + to glue a few strings, * to repeat a string, and f-strings to format values neatly. When joining many pieces (e.g., a list of words), use str.join.

Concatenation with `+`

Use + to join a small number of strings. If you need to combine text with numbers, convert the number or use an f-string.


              1234567891011
            
# Creating a personalized game message
player_first = "Alice"
player_last = "Johnson"
greeting = player_first + " " + player_last  # "Alice Johnson"

score = 10
# "Score: " + score  # TypeError → number must be converted to string
score_message = "Score: " + str(score)       # "Score: 10"

print(greeting)
print(score_message)

Repetition with `*`

Multiply a string by an integer to repeat it.


              12345
            
echo = "ha" * 3          # "hahaha"
rule = "-" * 10          # "----------"

print(echo)
print(rule)

Joining Many Pieces with `"sep".join(...)`

join is ideal when you have an iterable (like a list) of strings.


              123456789
            
# Building a message and a log entry from list data
message_parts = ["Welcome", "to", "Codefinity!"]
welcome_message = " ".join(message_parts)  # "Welcome to Codefinity!"

log_lines = ["User ID: 42", "Status: OK", "Process: Done"]
log_block = "\n".join(log_lines)           # "User ID: 42\nStatus: OK\nProcess: Done"

print(welcome_message)
print(log_block)

Basic Formatting with `f-strings`

An f-string evaluates expressions inside {} and inserts the result. It's concise and handles type conversion automatically.


              1234
            
# Displaying a progress message for a team member
name = "Ada"
tasks = 3
print(f"{name} completed {tasks} tasks.")   # "Ada completed 3 tasks."

Numeric formatting (common cases).


              123456
            
# Calculating the total cost of an online purchase
item_price = 12.5
tax_rate = 0.2
total_cost = item_price * (1 + tax_rate)

print(f"Total to pay: ${total_cost:.2f}")  # Rounded to 2 decimal places, e.g. "Total to pay: $15.00"

If you need a literal brace, double it.


              1
            
print(f"Use {{}} for placeholders.")  # "Use {} for placeholders."

Note

For long loops that build big strings, collect pieces and then ''.join(pieces).

Все було зрозуміло?

Дякуємо за ваш відгук!

Секція 1. Розділ 17

Запитати АІ

Запитайте про що завгодно або спробуйте одне із запропонованих запитань, щоб почати наш чат

Секція 1. Розділ 17

Concatenation, Repetition, and Basic Formatting

Concatenation with `+`

Repetition with `*`

Joining Many Pieces with `"sep".join(...)`

Basic Formatting with `f-strings`

1. You have `items = ["red", "green", "blue"]`. Which is the best way to produce `"red, green, blue"`?

2. What does `"ha" * 2 + "!"` produce?

3. Which line prints a price with two decimal places if `total = 7.5`?

Concatenation, Repetition, and Basic Formatting

Concatenation with +

Repetition with *

Joining Many Pieces with "sep".join(...)

Basic Formatting with f-strings

1. You have items = ["red", "green", "blue"]. Which is the best way to produce "red, green, blue"?

2. What does "ha" * 2 + "!" produce?

3. Which line prints a price with two decimal places if total = 7.5?

Concatenation with `+`

Repetition with `*`

Joining Many Pieces with `"sep".join(...)`

Basic Formatting with `f-strings`

1. You have `items = ["red", "green", "blue"]`. Which is the best way to produce `"red, green, blue"`?

2. What does `"ha" * 2 + "!"` produce?

3. Which line prints a price with two decimal places if `total = 7.5`?