Kindergarten Adventures

Another use case of a range array.

Kindergarten Adventures


Kindergarten Adventures | HackerRank
Help Meera collect the drawings in a way that lets as many students finish as is possible.



Prepare an array of length n, called range array alongside the input array.

1st iteration

t[1]=5. Calculate the range of possible x, the starting point for Meera which lets student 1 finish their drawing when she comes to them. In this case, it is from 2 to 5. So update the range array as rangeArray[2]++ and rangeArray[6]--.

2nd and 3rd iterations

Do the same thing as we did in the first iteration for the rest of the iterations.

4th iteration

Note that, the range of possible x crosses over the 1st student. In order to represent this in the range array, we not only increment rangeArray[5] but also rangeArray[1].

All the iterations

Summarizing Step

Calculate the running sum for the range array. The answer is the index of the maximum number in the running sum array.