Alice is very confident about her Vocabulary, according to her $lively$ words are those which contain only characters $A,B,C$ and the frequency of each of them should be the same. Alice has a word $\textit{S}$ of $1999998$ characters (A,B,C each occur 666666 times). Now Bob has a word $\textit{T}$ (which is lively as well) and he wants to know the minimum number of moves he needs to make in order to change the word from S to T in the worst case (irrespective of the words S and T). In a single move Bob can only swap neighboring letters. Report the answer divided 2 $modulo$ $1000000007$.