Autofill only non-empty cells in a column (excel) and skip filled cells

Question

i want to fill A1:A200 with the number '12'. In this column, some cells are pre-filled with values e.g. A20 contains the number '3' etc. I want these pre-filled values to remain instead of being overwritten by autofill. How can I do this?

Answer 1

High light the entire range A1:A200, then press Control+G, click Special, check Blanks, then press OK. Now that only the blank cells are highlighted, type the number 12 and then press Control+Enter. This will enter the number 12 into all the blank cells.