Iterating over a list

Iterating (遍历、迭代) over a list is a core programming concept where you access each element in a sequence individually to perform an operation, such as printing or transforming data

While loop method

while-loop-iterate-list.py

# Add 1 on each of the number in a list
original_list = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

# add all of the element by 1
index_of_list = 0

while index_of_list < len(original_list):
    original_list[index_of_list] += 1
    index_of_list += 1

print(original_list)

Results:

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

For loop method

for-loop-iterate-list.py

# Add 1 on each of the number in a list
original_list = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

# add all of the element by 1
for i in original_list:
    original_list[i] += 1

print(original_list)

Results:

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

Comprehensive usage

• Find odd and even number from the list and store them in a seperated variable name and print them at the end.
• Find odd number by using for loop method.
• Find even number by using while loop method.

comprehensive-list-iterate.py

num_list = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

odd_num_list = []
even_num_list = []

# odd - for loop
# control item
# i for the item in a list
for item in num_list:
    if item % 2 != 0:
        odd_num_list.append(item)

# even - while loop
# control index
index_of_list = 0

while index_of_list < len(num_list):
    if num_list[index_of_list] % 2 == 0:
        even_num_list.append(num_list[index_of_list])
    index_of_list += 1


print(f"Odd Number: {odd_num_list}")
print(f"Even Number: {even_num_list}")

Results:

Odd Number: [1, 3, 5, 7, 9]
Even Number: [2, 4, 6, 8, 10]

Conclusion