Python For Loop

A for loop is used to iterate over a sequence such as a list, tuple, string, dictionary, or range.

Unlike a while loop, a for loop is commonly used when the number of iterations is known.

Syntax

for item in sequence:
    # code block

Loop Through a List

Example:

fruits = ["Apple", "Banana", "Mango"]

for fruit in fruits:
    print(fruit)

Output:

Apple
Banana
Mango

Loop Through a String

Example:

for char in "Python":
    print(char)

Output:

P
y
t
h
o
n

Using the range() Function

The range() function generates a sequence of numbers.

Example:

for i in range(5):
    print(i)

Output:

0
1
2
3
4

range() with Start and Stop

Example:

for i in range(1, 6):
    print(i)

Output:

1
2
3
4
5

range() with Step

Example:

for i in range(0, 11, 2):
    print(i)

Output:

0
2
4
6
8
10

Break Statement

The break statement stops the loop immediately.

Example:

fruits = ["Apple", "Banana", "Mango"]

for fruit in fruits:
    if fruit == "Banana":
        break

    print(fruit)

Output:

Apple

Continue Statement

The continue statement skips the current iteration and continues with the next one.

Example:

fruits = ["Apple", "Banana", "Mango"]

for fruit in fruits:
    if fruit == "Banana":
        continue

    print(fruit)

Output:

Apple
Mango

Else Statement

The else block executes when the loop finishes normally.

Example:

for i in range(3):
    print(i)
else:
    print("Loop Finished")

Output:

0
1
2
Loop Finished

Nested For Loops

A for loop can be placed inside another for loop.

Example:

colors = ["Red", "Blue"]
fruits = ["Apple", "Banana"]

for color in colors:
    for fruit in fruits:
        print(color, fruit)

Output:

Red Apple
Red Banana
Blue Apple
Blue Banana

Loop Through a Dictionary

Example:

person = {
    "name": "John",
    "age": 25
}

for key in person:
    print(key, person[key])

Output:

name John
age 25

Using enumerate()

The enumerate() function adds a counter to an iterable.

Example:

fruits = ["Apple", "Banana", "Mango"]

for index, fruit in enumerate(fruits):
    print(index, fruit)

Output:

0 Apple
1 Banana
2 Mango

Practical Example

Print the multiplication table of 5.

Example:

for i in range(1, 11):
    print(f"5 x {i} = {5 * i}")

Output:

5 x 1 = 5
5 x 2 = 10
5 x 3 = 15
5 x 4 = 20
5 x 5 = 25
5 x 6 = 30
5 x 7 = 35
5 x 8 = 40
5 x 9 = 45
5 x 10 = 50

Summary

• A for loop is used to iterate over a sequence.
• It works with lists, tuples, strings, dictionaries, and ranges.
• The range() function generates a sequence of numbers.
• Use break to stop a loop.
• Use continue to skip an iteration.
• Use else to execute code after the loop completes.
• Nested loops allow looping inside another loop.