#Excel VBA, 127 bytes
Function z(w)
z=""
For Each x In w.Cells
v=x.value
For y=1To Len(z)
v=Replace(v,Mid(z,y,1),"",1,1)
Next
z=z&v
Next
End Function
Takes input in the form of an excel range.
#Excel VBA, 127 bytes
Function z(w)
z=""
For Each x In w.Cells
v=x.value
For y=1To Len(z)
v=Replace(v,Mid(z,y,1),"",1,1)
Next
z=z&v
Next
End Function
Takes input in the form of an excel range.