As any experienced programmer must know the famous problem of "Edit Distance", however this problem is considered an “alternating chain” if you have alternately made case sensitive.
Example: "AaAaAbB" "B" "a" "aBaCdEf"
Alternating chains are considered in our problem.
We only have one operation that is permitted in exchange for a lower or upper case Latin letter.
Given a string giving the minimum number of changes to be considered an alternating chain.
A string with no spaces line containing only uppercase and lowercase letters, one for each line of maximum length 10^3 until end of file
For each line print the minimum number of changes to the chain is a "chain alternately"
Input: AaAaB ABaa a Output: 0 2 0