You can also try this one
complete the formula by pressing CTRL_SHIFT+ENT
=IF(ISBLANK(A1),"",INDEX($A$1:$A$10,MATCH(SMALL(1*MID($A$1:$A$10,2,FIND("-",$A$1:$A$10)-2),ROW(A1)),1*MID($A$1:$A$10,2,FIND("-",$A$1:$A$10)-2),0)))
R6-1.F
R1-1.A
6
R1-1.A
R7-1.G
R2-1.B
7
R2-1.B
R3-1.C
R3-1.C
3...