A suburban street consists of n homes arranged in a row, each painted black or white. You are given a string input of length n$,$ such that the ith character is $\text{'}$B$\text{'}$ if the ith house is black and $\text{'}$W$\text{'}$ if the ith house is white.

You consider the homes appealing if all black houses appear before all white houses OR if all white houses appear before all black houses. As a skilled painter, it takes you one day to repaint any one of the houses any color of your

Choice.

Write a function that takes the input string and returns an integer, the minimum number of days it will take to make the homes appealing. The input string is guaranteed to contain at most $50$ characters.