SPOJ Problem Set (classical)
10537. Edit Distance Again
Problem code: EDIT

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.
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.
Input
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
Output
For each line print the minimum number of changes to the chain is a "chain alternately"
Example
Input:
AaAaB
ABaa
a
Output:
0
2
0