"a b c d e"
"a b c d e"
-1

=> 1,0

-----------------------------

"a b c d e"
"a b d e"
-1

=> 0.7499999999999999

-----------------------------

"a b c d e"
"a b d e"
1

=> 0.5714285714285715

-----------------------------

"a a a a a"
"a a b a a"
-1

=> 0.6

-----------------------------

"a a a a a"
"a a b a a"
2

=> 0.42857142857142855

-----------------------------

"a b a b a"
"b a b a b"
-1

=> 0.8000000000000002

-----------------------------

"a b a b a"
"b a b a b"
3

=> 0.8888888888888888


-----------------------------

"a b a b a"
"B a B a B"
3

=> 0.8888888888888888


-----------------------------

"a3b3a.b,a"
"b5a4b3a2b"
3

=> 0.8888888888888888