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## Microsoft Interview Riddles

With the help of our readers, along with some careful research, we've collected this set of riddles that have been given to candidates interviewing for jobs at Microsoft. Founded way back in 1975, Microsoft is the home of many brilliant minds, some of whom probably had to figure out a few of these riddles to get their jobs. Don't be fooled though: these Microsoft interview puzzles aren't easy. If you've never seen them before, try to figure them out without peeking at the solutions. And if you've heard of any Microsoft interview riddles that aren't on this list, let us know by emailing us (info at bigriddles dot com) or by posting them on the riddles forum.

You have two lengths of rope. Each rope has the property that if you light it on fire at one end, it will take exactly 60 minutes to burn to the other end. Note that the ropes will not burn at a ...
Ten pirates find a buried treasure of 100 pieces of gold. The pirates have a strict ranking in their group: Pirate 1 is the lead pirate, Pirate 2 is second-in-command, Pirate 3 is the third most ...
The King calls in three wise men and tells them to all close their eyes. While their eyes are closed, he goes around and puts a hat on each of them. "I put a blue or white hat on each of you," the ...
Two trains are traveling toward each other on the same track, each at 60 miles per hour. When they are exactly 120 miles apart, a fly takes off from the front of one of the trains, flying toward the ...
There is a prison with 100 prisoners, each in separate cells, which are sealed off, soundproof and windowless. There is a lobby in the prison with a lightbulb in it. Each day, the warden will pick ...
Two robots are placed at different points on a straight line of infinite length. When they are first placed down, they each spray out some oil to mark their starting points. You must program each ...
Two words are anagrams if and only if they contain the exact same letters with the exact same frequency (for example, "name" and "mean" are anagrams, but "red" and "deer" are not). Given two strings ...
You stand before a 100-story building with two eggs. Using only these two eggs, you must figure out the highest floor from which you can drop an egg such that the egg won't break when it hits the ...
There are 1 million closed school lockers in a row, labeled 1 through 1,000,000. You first go through and flip every locker open. Then you go through and flip every other locker (locker 2, 4, 6, ...
Your friend pulls out a perfectly circular table and a sack of quarters, and proposes a game. "We'll take turns putting a quarter on the table," he says. "Each quarter must lay flat on the table, and ...
You have twelve balls, identical in every way except that one of them weighs slightly less or more than the balls. You have a balance scale, and are allowed to do 3 weighings to determine which ball ...
A swan sits at the center of a perfectly circular lake. At an edge of the lake stands a ravenous monster waiting to devour the swan. The monster can not enter the water, but it will run around the ...
People are waiting in line to board a 100-seat airplane. Steve is the first person in the line. He gets on the plane but suddenly can't remember what his seat number is, so he picks a seat at random. ...
You are visiting NYC when a man approaches you. "Not counting bald people, I bet a hundred bucks that there are two people living in New York City with the same number of hairs on their heads," he ...
Why are manhole covers round? Do manhole covers really need to be circular?