Merge and update methods in Ruby - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to merge two hashes using the merge method.

Ruby

hash1 = {a: 1, b: 2}
hash2 = {b: 3, c: 4}
result = hash1.[1](hash2)
puts result

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

Aupdate

Bcombine

Cmerge

Dconcat

Attempts:

3 left

💡 Hint

Common Mistakes

Using update instead of merge changes the original hash.

The merge method combines two hashes and returns a new hash without modifying the original.

2fill in blank

medium

Complete the code to update a hash with another hash using the update method.

Ruby

hash1 = {x: 10, y: 20}
hash2 = {y: 30, z: 40}
hash1.[1](hash2)
puts hash1

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

Aupdate

Bmerge

Creplace

Dconcat

Attempts:

3 left

💡 Hint

Common Mistakes

Using merge instead of update does not change the original hash.

The update method modifies the original hash by adding or replacing keys from another hash.

3fill in blank

hard

Fix the error in the code to correctly merge two hashes with a block to handle conflicts.

Ruby

h1 = {a: 100, b: 200}
h2 = {b: 254, c: 300}
result = h1.merge(h2) { |key, old_val, new_val| [1] }
puts result

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

Aold_val * new_val

Bold_val - new_val

Cnew_val - old_val

Dold_val + new_val

Attempts:

3 left

💡 Hint

Common Mistakes

Using subtraction or multiplication changes the intended result.

The block tells merge how to combine values when keys overlap. Here, it adds the old and new values.

4fill in blank

hard

Fill both blanks to create a hash comprehension that merges two hashes and keeps the larger value for duplicate keys.

Ruby

h1 = {a: 5, b: 10}
h2 = {b: 7, c: 12}
result = h1.merge(h2) { |[1], old_val, new_val| old_val [2] new_val ? old_val : new_val }
puts result

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

Akey

Bk

Cx

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names or comparison operators.

The block compares old and new values and keeps the larger one. The first blank is the block variable for the key, usually key. The second blank is the comparison operator >.

5fill in blank

hard

Fill all three blanks to update a hash with another hash, but keep the original value if the new value is nil.

Ruby

h1 = {a: 1, b: 2}
h2 = {b: nil, c: 3}
h1.update(h2) { |[1], old_val, new_val| new_val [2] nil ? new_val : [3] }
puts h1

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

Akey

B!=

Cold_val

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using == instead of != causes wrong logic.

Returning new_val when it is nil replaces original value incorrectly.

The block checks if the new value is not nil. If so, it uses the new value; otherwise, it keeps the old value. The first blank is the block variable for the key, usually key. The second blank is the not equal operator !=. The third blank is old_val to keep the original value.