tr for character transformation in Bash Scripting - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to convert all lowercase letters in the input to uppercase using tr.

Bash Scripting

echo "hello world" | tr [1]

Drag options to blanks, or click blank then click option'

A"a-z A-Z"

B"a-z" "A-Z"

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to quote the character sets.

Swapping the order of character sets.

The tr command uses the syntax tr 'a-z' 'A-Z' to convert lowercase letters to uppercase.

2fill in blank

medium

Complete the code to replace all spaces with underscores using tr.

Bash Scripting

echo "hello world" | tr [1]

Drag options to blanks, or click blank then click option'

A" _"

C" " "_"

Attempts:

3 left

💡 Hint

Common Mistakes

Not quoting the space character.

Using the wrong order of characters.

The tr command replaces characters from the first set with those in the second set. Here, spaces are replaced with underscores.

3fill in blank

hard

Fix the error in the code to delete all digits from the input using tr.

Bash Scripting

echo "abc123def" | tr -d [1]

Drag options to blanks, or click blank then click option'

A"0-9"

B"a-z"

C"A-Z"

D"1-9"

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect character ranges like 1-9 which misses zero.

Trying to delete letters instead of digits.

The -d option deletes characters. To delete digits, use the range 0-9.

4fill in blank

hard

Fill both blanks to replace all vowels with the letter 'x' using tr.

Bash Scripting

echo "hello world" | tr [1] [2]

Drag options to blanks, or click blank then click option'

A"aeiou"

B"xyz"

C"x"

D"aeiouAEIOU"

Attempts:

3 left

💡 Hint

Common Mistakes

Not including uppercase vowels.

Using multiple characters in the replacement set.

To replace vowels (both lowercase and uppercase) with 'x', use tr 'aeiouAEIOU' 'x'.

5fill in blank

hard

Fill all three blanks to create a dictionary that maps each word to its length, but only for words longer than 3 characters.

Bash Scripting

words=("apple" "bat" "cat" "dog" "elephant")
for word in "${words[@]}"; do
  if [[ ${#word} [1] [2] ]]; then
    echo "${word}: $[3]"
  fi
done

Drag options to blanks, or click blank then click option'

A>

B3

C${#word}

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using less than instead of greater than.

Printing the word instead of its length.

The code checks if the length of the word is greater than 3, then prints the word and its length.