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Conditional Statements (if, elif, else)
Conditional statements allow your code to execute different actions based on certain conditions.
if
: Checks a condition and executes a block of code if it evaluates toTrue
.
if condition:
# code to execute
elif
: Short for “else if,” checks another condition if the previousif
condition wasFalse
.
elif another_condition:
# code to execute
else
: Executes a block of code if none of the preceding conditions wereTrue
.
else:
# code to execute
Example:
age = 20
if age < 13:
print("Child")
elif 13 <= age < 20:
print("Teenager")
else:
print("Adult")
Loops (for, while)
Loops allow you to execute a block of code repeatedly.
for
Loop: Iterates over a sequence (e.g., a list, tuple, string).
for item in sequence:
# code to execute
Example:
for i in range(5):
print(i)
- while Loop: Repeats as long as a condition is True.
while condition:
# code to execute
Example:
count = 0
while count < 5:
print(count)
count += 1
Comprehensions (list, dictionary, and set comprehensions)
Comprehensions provide a concise way to create lists, dictionaries, and sets.
- List Comprehensions: Create a new list by applying an expression to each item in an existing iterable.
[expression for item in iterable]
Example:
squares = [x**2 for x in range(10)]
- Dictionary Comprehensions: Create a new dictionary by applying an expression to each item in an existing iterable.
{key_expression: value_expression for item in iterable}
Example:
square_dict = {x: x**2 for x in range(10)}
- Set Comprehensions: Create a new set by applying an expression to each item in an existing iterable.
{expression for item in iterable}
Example:
square_set = {x**2 for x in range(10)}
Let me know if you need further explanations or examples on any of these topics!