Excel version reference: 20 10
1, for example 1: A 1-A2-A3-A4 (continuous cells)
Then the formula =A 1-SUM(A2:A4) can be used.
2. Example 2: A2-A4-A5-7 (Discontinuous)
Then =sum(A2, -A4, -A5, -7) can be used.