Control Flow
Control flow allows your program to make decisions and repeat blocks of code. In Python, control flow is defined by indentation.
1. If-Else Conditionals
age = 18
if age >= 21:
print("Welcome to the club")
elif age >= 18:
print("Welcome to the cafe")
else:
print("Access Denied")
2. While Loops
Repeats a block of code as long as a condition is True.
count = 0
while count < 5:
print(f"Count is: {count}")
count += 1
3. For Loops
Used for iterating over a sequence (list, tuple, string) or a range.
# Iterating over a range
for i in range(5):
print(i) # 0 to 4
# Iterating over a list
fruits = ["Apple", "Banana", "Cherry"]
for fruit in fruits:
print(fruit)
4. Break & Continue
- break: Stops the loop entirely.
- continue: Skips the current iteration and moves to the next.
for n in range(10):
if n == 5:
break # stops at 5
if n % 2 == 0:
continue # skips evens
print(n)
Syntactic Sugar: Python also has a unique for...else construction where the else block runs if the loop finished normally (without a break).