Modular Arithmetic Basics in DSA Python - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to compute the remainder when 17 is divided by 5.

DSA Python

result = 17 [1] 5
print(result)

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

A%

B//

C*

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using // instead of % returns the quotient, not remainder.

The % operator gives the remainder of division, which is the core of modular arithmetic.

2fill in blank

medium

Complete the code to check if 23 is divisible by 7 using modular arithmetic.

DSA Python

if 23 [1] 7 == 0:
    print("Divisible")
else:
    print("Not divisible")

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

A//

B%

C*

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using // returns quotient, not remainder.

Using % checks the remainder. If remainder is 0, the number is divisible.

3fill in blank

hard

Fix the error in the code to correctly compute (a + b) mod m.

DSA Python

a = 10
b = 15
m = 6
result = (a [1] b) % m
print(result)

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

A*

B-

C+

D//

Attempts:

3 left

💡 Hint

Common Mistakes

Using - or * changes the operation meaning.

To add numbers before taking modulo, use the plus operator +.

4fill in blank

hard

Fill both blanks to create a dictionary of numbers and their squares modulo 5 for numbers 1 to 5.

DSA Python

squares_mod = {x: (x [1] x) [2] 5 for x in range(1, 6)}
print(squares_mod)

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

A*

B+

C%

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using + instead of * changes the operation.

Use * to multiply x by itself, then % to take modulo 5.

5fill in blank

hard

Fill all three blanks to create a dictionary with keys as numbers squared modulo 7 and values as the original numbers for 1 to 6.

DSA Python

result = [1]: [2] for [3] in range(1, 7)}
print(result)

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

Ax**2 % 7

Bx

Di

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently.

Keys are squares modulo 7 (x**2 % 7), values are original numbers (x), and loop variable is x.