Insertion Sort Algorithm in DSA Go - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to start the outer loop from the second element in the array.

DSA Go

for i := [1]; i < len(arr); i++ {
    key := arr[i]
    j := i - 1
    for j >= 0 && arr[j] > key {
        arr[j+1] = arr[j]
        j--
    }
    arr[j+1] = key
}

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

A0

B-1

C1

Dlen(arr)

Attempts:

3 left

💡 Hint

Common Mistakes

Starting the loop at 0 causes unnecessary comparisons.

Starting at len(arr) causes the loop to never run.

The insertion sort starts from the second element (index 1) because the first element is considered sorted.

2fill in blank

medium

Complete the code to move elements greater than the key one position ahead.

DSA Go

for j := i - 1; j >= 0 && arr[j] [1] key; j-- {
    arr[j+1] = arr[j]
}

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

A<

B<=

C==

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' will move smaller elements incorrectly.

Using '==' will not move any elements.

We move elements that are greater than the key to the right to make space for the key.

3fill in blank

hard

Fix the error in placing the key after shifting elements.

DSA Go

arr[[1]] = key

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

Aj+1

Bi

Cj-1

Dj

Attempts:

3 left

💡 Hint

Common Mistakes

Using j places the key in the wrong position.

Using i places the key at the current outer loop index without adjustment.

After the inner loop, j is decremented one extra time, so the correct position is j+1.

4fill in blank

hard

Fill both blanks to complete the inner loop condition and decrement.

DSA Go

for j := i - 1; j [1] 0 && arr[j] > key; j[2] {
    arr[j+1] = arr[j]
}

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

A>=

B<=

C--

D++

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<=' causes the loop to run incorrectly.

Using '++' increments j, which is wrong here.

The loop continues while j is greater or equal to 0 and arr[j] is greater than key. We decrement j each time.

5fill in blank

hard

Fill all three blanks to create a function that sorts an array using insertion sort.

DSA Go

func [1](arr []int) {
    for i := [2]; i < len(arr); i++ {
        key := arr[i]
        j := i - 1
        for j >= 0 && arr[j] > key; j[3] {
            arr[j+1] = arr[j]
        }
        arr[j+1] = key
    }
}

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

AInsertionSort

B1

C--

DSortArray

Attempts:

3 left

💡 Hint

Common Mistakes

Starting outer loop at 0.

Using '++' instead of '--' for j.

Using unclear function names.

The function is named InsertionSort. The outer loop starts at 1. The inner loop decrements j with '--'.