When corresponding values are both TRUE, the result is 1.
In any other case, the result is 0.
At this point, we have collected an array that represents all Red victories when Red isTeam1.
This covers the left side of the logic inside SUMPRODUCT.
We do this because we are counting Red wins asTeam1ORTeam2.
The complete formula is:
The LEN function is checking for any characters.
When LEN returns zero, it means a cell is empty.
