Problems
Queen Move
Queen Move
There is a queen on the chessboard of size $m × n$. How many squares does the queen attack?
\InputFile
Four positive integers: the size of the chessboard $m$ and $n$ and the queen's coordinates $x$ and $y~(1 \le x \le m \le 10^9, 1 \le y \le n \le 10^9)$.
\OutputFile
Print the number of squares the queen attacks.
Input example #1
8 8 4 5
Output example #1
27
Input example #2
1000000000 3 999999999 2
Output example #2
1000000005