100 doors to be painted
You have 100 doors to be painted and 2 painters. 1 starts at one end and paints every other door. […]
Logic Puzzles
Logic Puzzles
Classic logic puzzles that challenge your reasoning abilities and creative thinking. From river crossing problems to complex constraint satisfaction, these puzzles develop the analytical mindset crucial for technical interviews.
Puzzle Categories:
Constraint satisfaction: Fox-chicken-grain, missionaries and cannibals
Information theory: Card tricks, encoding problems
Optimization: Minimum steps, optimal strategy
Combinatorics: Counting arrangements, permutations
Solution Approaches:
State space search (BFS/DFS)
Backward reasoning
Constraint elimination
Mathematical modeling
Companies: Google, Microsoft, Palantir, Dropbox frequently use logic puzzles to assess problem-solving skills.
Logic Puzzles
Three People on a Weak Bridge
Three people need to cross a weak bridge at night. They have just one turn and the bridge is only
Logic Puzzles
Out of 10 Coins
Out of 10 coins, one weighs less then the others. You have a scale. How will you determine which one
Logic Puzzles
Getting a fair result with an unfair coin
How can you get a fair coin toss if someone hands you a coin that is weighted to come up
Brain Teasers, Logic Puzzles
100 Doors in a Row
Problem: you have 100 doors in a row that are all initially closed. you make 100 passes by the doors
Brain Teasers, Data Structures, Dynamic Programming, Logic Puzzles
Red Marbles, Blue Marbles
Problem: you have two jars, 50 red marbles, 50 blue marbles. you need to place all the marbles into the
Algorithms, Brain Teasers, Logic Puzzles
Bumblebee
problem: two trains enter a tunnel 200 miles long (yeah, its a big tunnel) travelling at 100 mph at the
Bit Manipulation, Brain Teasers, Logic Puzzles
Daughters’ Ages
Two MIT math grads bump into each other at Fairway on the upper west side. They haven’t seen each other
Algorithms, Dynamic Programming, Logic Puzzles, String Manipulation
Palindromes
Problem: this year on October 2, 2001, the date in MMDDYYYY format will be a palindrome (same forwards as backwards).10/02/2001when
Algorithms, Bit Manipulation, Brain Teasers, Logic Puzzles, Math Problems, Recursion
Sum it Up
Problem: you are given a sequence of numbers from 1 to n-1 with one of the numbers repeating only once.
Brain Teasers, Logic Puzzles
Pirates
Five pirates have 100 gold coins. they have to divide up the loot. in order of seniority (suppose pirate 5
Bit Manipulation, Brain Teasers, Logic Puzzles, String Manipulation, System Design
Fog Creek Programmers
100 fogcreek programmers are lined up in a row by an assassin. the assassin puts red and blue hats on them.
Bit Manipulation, Brain Teasers, Logic Puzzles
Bad King
A bad king has a cellar of 1000 bottles of delightful and very expensive wine. A neighbouring queen plots to
Brain Teasers, Logic Puzzles, Microsoft Interview Questions
Bridge
Problem: this one is a classic that many of you have probably already heard, but all the more reason why
Algorithms, Bit Manipulation, Brain Teasers, Logic Puzzles, Math Problems, System Design
Card Trick Without the Trick
This is a card trick without the trick. there is no sleight of hand, no tricks up my sleeve, no