Engineering & Computer Science Challenges

Welcome to the Engineering Puzzle Challenge! 🏗️🧩
Solve 5 puzzles in sequence. Each puzzle has a numeric answer.

Your time will track how quickly you solve the puzzles, but don’t worry, it’s just for fun!

Start the Challenge →

Four engineers must cross a bridge at night with one flashlight. Only two people can cross at once, and someone must bring the flashlight back if needed.

Crossing speeds:
A = 1 min, B = 2 min, C = 7 min, D = 10 min

When two cross together, they walk at the slower person's speed.

Enter the minimum total time (in minutes) required for all four engineers to cross the bridge.

Submit

You have 12 identical-looking balls. Eleven weigh the same, and one ball is slightly heavier.

Using only a balance scale, determine the minimum number of weighings required to guarantee identifying the heavier ball.

Enter the number of weighings needed.

Submit

You have 100 lights, all initially off.

Pass 1: Toggle every light
Pass 2: Toggle every 2nd light
Pass 3: Toggle every 3rd light
Continue this pattern until pass 100.

After all passes, how many lights remain on? 
Hint: Lights toggled an odd number of times stay on.

Submit

You have 2 identical eggs and a 100-floor building.

An egg will break if dropped from the critical floor or any floor above it.

What is the minimum number of drops required to guarantee finding the critical floor, in the worst-case scenario?

Hint: Plan your drops to balance the risk between the first and second egg.

Submit

Examine the sequence below and enter the next number:

2, 3, 5, 9, 17, ...

Hint: Look at how the differences between consecutive numbers change.

Submit

Welcome to the Computer Science Puzzle Challenge! 💻🧩
Tackle 5 programming and logic puzzles in order. Each puzzle has a numeric answer.

Your time will be recorded, but remember, it’s all about having fun and testing your problem-solving skills!

Start the Challenge →

Add the binary numbers 1011 and 1101. Enter the decimal equivalent of the sum.

Submit

Using bubble sort on the array [3,1,4,2], how many swaps are required to sort the array in ascending order? Count every pair swap until fully sorted.

Submit

A message is sent from computer A to D, passing through B and C. Each hop adds 5ms latency. How much total time does the message take from A → D?

Submit

How many times does the inner statement execute in the loop below?

for(i=0; i<5; i++){
    for(j=0;j<3;j++){
        // do something
    }
}
        

Submit

Find the next number in this sequence: 1, 2, 4, 8, 16, .... Hint: look for a pattern in powers.

Submit