Bubble sort is a sorting algorithm that consists of a number of rounds. On each round the algorithm scans the array from left to right and swaps any adjacent elements that are in the wrong order.
Given an array of $n$ integers, calculate the number of bubble sort rounds needed to sort the array.
The first line has an integer $n$ : the array size.
The next line has $n$ integers $x_1,x_2,\dots,x_n$ : the array contents.
Print one integer: the number of rounds.
5 3 2 4 1 4\n · · · · \n
3\n
Bubble sort needs three rounds to sort this array. The array contents after each round are $[2,3,1,4,4]$ , $[2,1,3,4,4]$ , and $[1,2,3,4,4]$ .