Effecient Algorithm Discussion

I have come to know about an interesting algorithm based question .
Question is as follws----

**I have two permutation of same string without any space …
EX— ASCBD and ACSDB

**I have to calulate minimum no of operation to make these string two permutation identical using the following operation —

  1. any character i of a string can be switched with its any one of its adjacent character .

Operations can take place in only one strng or on both the strings.

I serching in the internet but find only BRUTE-FORCE…Kindly suggest me a effecient approach …??

http://stackoverflow.com/questions/7797540/counting-the-swaps-required-to-convert-one-permutation-into-another Hope it helps !

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