Tech Interview with Live Coding on 'collabedit' - three rounds, about an hour each, on one of GrabTaxi Singapore's Superdays.

First round was a string manipulation question. The second round was related to the usage of data structures (queues, heaps, time complexity questions). For collabedit, you could choose which language to code in; I chose Java. Both the first two rounds involved coding on collabedit.

The third round involved an array with elements from 1 to n, where one element is missing and another is duplicated. The task was to find the duplicate and the missing element, as well as designing a URL shortener.

Helpful HR.

Format a string of numbers to display currency. For example, "1234.678" should become "1,234.68".