Copy special characters to a new list

Write a Python program to copy the special characters from a list into an empty list.

["s", "2", "4", "6", "a", "@", "!", "%", "#"]

['@', '!', '%', '#']

Approach

1. Keep items that are not letters or digits.

Solution

a = ["s", "2", "4", "6", "a", "@", "!", "%", "#"]b = []for ch in a:    if not ch.isalnum():        b.append(ch)print(b)

['@', '!', '%', '#']

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Copy odd numbers to a new list

Write a Python program to copy the odd numbers from a list into an empty list.

[3, 8, 5, 0, 2, 7]

[3, 5, 7]

Approach

1. Append numbers with remainder 1.

Solution

a = [3, 8, 5, 0, 2, 7]b = [n for n in a if n % 2 == 1]print(b)

[3, 5, 7]

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Copy even numbers to a new list

Write a Python program to copy the even numbers from a list into an empty list.

[2, 3, 5, 76, 9, 0, 16]

[2, 76, 0, 16]

Approach

1. Append numbers with remainder 0.

Solution

a = [2, 3, 5, 76, 9, 0, 16]b = []for n in a:    if n % 2 == 0:        b.append(n)print(b)

[2, 76, 0, 16]

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Count special characters

Write a Python program to count the special characters (not letters, digits or spaces) in a string.

"@sqa#tools!!"

4

Approach

1. A special character is not alphanumeric and not a space.

Solution

text = "@sqa#tools!!"count = 0for ch in text:    if not ch.isalnum() and not ch.isspace():        count += 1print(count)

4

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Days of the week except Sunday

Write a Python program to print the days of the week except Sunday using a while loop.

Monday
Tuesday
Wednesday
Thursday
Friday
Saturday

Approach

1. Walk through a list with an index and skip “Sunday”.

Solution

days = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"]i = 0while i < len(days):    if days[i] != "Sunday":        print(days[i])    i += 1

Monday
Tuesday
Wednesday
Thursday
Friday
Saturday

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1 to 10 except 5 and 6 with while

Write a Python program to print 1 to 10 except 5 and 6 using a while loop.

1
2
3
4
7
8
9
10

Approach

1. Increase the counter before continue, otherwise the loop never ends.

Solution

n = 0while n < 10:    n += 1    if n in (5, 6):        continue    print(n)

1
2
3
4
7
8
9
10

Line by line

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Product of the first 10 numbers

Write a Python program to find the product of the first 10 natural numbers.

3628800

Approach

1. Start at 1 and multiply by each number.

Solution

product = 1for n in range(1, 11):    product *= nprint(product)

3628800

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Sum of the first 10 numbers with while

Write a Python program to find the sum of the first 10 natural numbers using a while loop.

55

Approach

1. Add a counter to a total until it passes 10.

Solution

i, total = 1, 0while i <= 10:    total += i    i += 1print(total)

55

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Table of 2 with a while loop

Write a Python program to print the table of 2 using a while loop.

2 x 1 = 2
2 x 2 = 4
2 x 3 = 6
2 x 4 = 8
2 x 5 = 10
2 x 6 = 12
2 x 7 = 14
2 x 8 = 16
2 x 9 = 18
2 x 10 = 20

Approach

1. Use a counter from 1 to 10.

Solution

i = 1while i <= 10:    print(f"2 x {i} = {2 * i}")    i += 1

2 x 1 = 2
2 x 2 = 4
2 x 3 = 6
2 x 4 = 8
2 x 5 = 10
2 x 6 = 12
2 x 7 = 14
2 x 8 = 16
2 x 9 = 18
2 x 10 = 20

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First 20 natural numbers with while

Write a Python program to print the first 20 natural numbers using a while loop.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 

Approach

1. Count from 1 to 20.

Solution

n = 1while n <= 20:    print(n, end=" ")    n += 1print()

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 

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