Practice · judged on hidden tests
Problems
14 problems, ordered so each topic builds on the last.
- Not startedArithmetic without bracketsStrings, Stacks and queuesMedium
- Not startedCancel out neighbouring pairsStrings, Stacks and queuesEasy
- Not startedHow long this price has been the bestStacks and queues, ArraysMedium
- Not startedHow long until every orange has gone badStacks and queues, Graphs, MatricesMedium
- Not startedHow long until it gets warmerStacks and queues, ArraysMedium
- Not startedReading a tree one level at a timeStacks and queues, TreesMedium
- Not startedThe biggest rectangle inside a histogramStacks and queues, ArraysHard
- Not startedThe first letter that has appeared only once, so farHash maps, Strings, Stacks and queuesMedium
- Not startedThe first negative number in every windowStacks and queues, Arrays, Sliding windowMedium
- Not startedThe largest number in every windowStacks and queues, Arrays, Sliding windowHard
- Not startedThe next bigger number to the rightStacks and queues, ArraysEasy
- Not startedValid parenthesesStrings, Stacks and queuesEasy
- Not startedWater held between the barsTwo pointers, Stacks and queues, ArraysHard
- Not startedWhat the tree looks like from the rightStacks and queues, TreesMedium