Emily has received a set of marbles as her birthday gift. She is trying to create a staircase shape with her marbles. A staircase shape contains k marbles in the kth row. Given n as the number of marbles help her to figure out the number of rows of the largest staircase she can make. For example a stair case of size 4 looks like: * * * * * * * * * * Table 0.1: Staircase of size 4