Facebook's toughest interview questions revealed

Facebook give their applicants some of the toughest questions out there! Job review site GlassDoor  has revealed a few of these unusual questions. 

How many can you answer? 

Find a needle in a haystack

Candidates have been asked to solve real-life problems with code talk. 

One was told: "Write a C function to define strstr(char *haystack, char * needle) to return the first occurrence of needle in haystack."

Heads or tails?

"Pick up a coin C1 given C1+C2 with probability of trials p(h1)=.7, p(h2)=.6 and doing 10 trials. "What is the probability that the given coin you picked is C1 given you have 7 heads and 3 tails?"

How many employees does it take to break a light bulb?

You have two lightbulbs and a 100-storey building," the candidate was told. "You want to find the floor at which the bulbs will break when dropped. Find the floor using the least number of drops."

Is it raining or not?

"You're about to get on a plane to Seattle. You want to know if you should bring an umbrella. "You call 3 random friends of yours who live there and ask each independently if it's raining.

"Each of your friends has a 2/3 chance of telling you the truth and a 1/3 chance of messing with you by lying. "All 3 friends tell you that 'Yes' it is raining. What is the probability that it's actually raining in Seattle?"

Extremely organised crime

"You are trying to rob houses on a street," one candidate was told. "Each house has some cash. Your goal is to rob houses such that you maximise the total robbed amount."

However on once a house is robbed the two houses next door aren't able to be broken into.

Get out of jail free

"How would you measure/calculate the rate of rehabilitation in Irish prisons?"

Big ambitions

"When and how Facebook will reach 2 billion users?"

Do you always dress like that? 

One disgruntled applicant to Facebook's California HQ complained they were asked: "Do you always dress like that?" "They send a lot of mixed messages," the candidate said. "The website states that you should dress business for the interview, but I was dissed by one of the staff for doing exactly that."  

Source: Mirror UK