Loops in Python

For

There are three main types of for loop in Python and they all use the for...in clause:

  1. Traditional for loop with range:

    for i in range(0, 5):
    print(i)

    This is equivalent to the following in JavaScript:

    for (let i = 0; i <= 5: i++) {
    console.log(i)
}

  2. for loop with iterable:

    fruits = ["apple", "banana", "cherry"]
for fruit in fruits:
    print(fruit)

  3. for loop with enumerate() function: Iterate over an iterable whilst also keeping track of the index of the current element:

    for index, fruit in enumerate(fruits):
    print(f"Index {index}: {fruit}")

Loop in increments greater than 1

The following loop increments by 2 on each iteration

for i in range(0, 10, 2):
    print(i, ' ', end='')
print()

# 0  2  4  6  8

Break and continue

Break

num = int(input('Enter a number from 1-6 to check for: '))
for i in range(0, 6):
    if i == num:
        break
    print(i, ' ')

Continue

for i in range(0, 10):
    print(i, ' ', end='')
    if i % 2 == 1:
        continue
    print('hey its an even number')
    print('we love even numbers')
print('Done')

"""
0  hey its an even number
we love even numbers
1  2  hey its an even number
we love even numbers
3  4  hey its an even number
we love even numbers
5  6  hey its an even number
we love even numbers
7  8  hey its an even number
we love even numbers
9  Done
"""

While

count = 0
print('Starting')
while count < 10:
    print(count, '', end='')
    count += 1

print()  # not part of the while loop
print('Done')

"""
Starting
0 1 2 3 4 5 6 7 8 9
Done
"""

There are no do while loops in Python

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