I applied to Pinterest by giving my resume to a recruiter in a career fair. The interview process took several weeks, and involved three phone interviews. In my interview I was asked to code the typical "look and say" problem, aka getting 1112223 as input and outputting 313213, and to code a duplicate removal algorithm. For the second one, I was asked to find the k most frequently used words in a string, and to do the first missing number problem. Finally, for the last one I had to implement a hash map and all its methods. The recruiters and interviewers were all amazing and really kind.