11608번 - Complexity 다국어

Define the complexity of a string to be the number of distinct letters in it. For example, the string string has complexity 6 and the string letter has complexity 4.

You like strings which have complexity either 1 or 2. Your friend has given you a string and you want to turn it into a string that you like. You have a magic eraser which will delete one letter from any string. Compute the minimum number of times you will need to use the eraser to turn the string into a string with complexity at most 2.

The input consists of a single line that contains a single string of at most 100 lowercase ASCII letters (‘a’–‘z’).

Print, on a single line, the minimum number of times you need to use the eraser.