Task:
You are given a rectangular board of size M × N cells. An unlimited number of standard dominoes of 2 × 1 squares are also given. Dominos can be rotated. It is required to put as many dominoes as possible on the board so that the following conditions are met:
- Each domino completely covers two squares of the board. 
- No two dominoes overlap. 
- Each domino is completely inside the board. Touching the edges of the permissions. 
Find the maximum number of dominoes that can be stacked with the given restrictions.
My CODE:
a = int(input())
b = int(input())
print(a*b // 2)
ERROR:
Traceback (most recent call last):
  File "program.pys3", line 1, in <module>
    a = int(input())
EOFError: EOF when reading a line
 
    