Minimum Moves to Make All Characters Identical

Given a string s, determine the minimum number of moves required to make all characters in the string the same. In one move, you can change a contiguous block of identical characters into any other single character.

Mathematically, if the string is represented as \(s_1 s_2 \ldots s_n\), the answer is given by:

\[ \text{moves} = \sum_{i=2}^{n} \mathbf{1}_{\{s_i \neq s_{i-1}\}}, \]

where \(\mathbf{1}_{\{s_i \neq s_{i-1}\}}\) is 1 if \(s_i \neq s_{i-1}\) and 0 otherwise.

Example: For s = "abbcaa", the moves are 3 since the characters change from 'a' to 'b', 'b' to 'c', and 'c' to 'a'.

inputFormat

The input is provided via standard input (stdin) as a single line containing the string s. The string can be empty, in which case the output should be 0.

outputFormat

Output a single integer representing the minimum number of moves required to make all characters in the string identical. The output is written to standard output (stdout).

abbcaa

3