TimeLimit : 1 Second   Memorylimit : 32 Megabyte   

Totalsubmit : 0   Accepted : 0

  Little White bought a new house recently. She doesn't like the design of the floor anyway, so she decides to decorate the floor. Now she has bricks of the 5 shapes below, all with an infinite amount. 

 
  Bricks may not overlap each other, and you cannot rotate them to fit in the "holes".
  Now, please tell Little White how many units can she cover using these bricks. 

Input 

  For every test case, you are given two integers n and m indicating the floor is an n*m rectangle 

consisting of n*m 1*1 grids.(1<=n<=100,1<=m<=6)
  Proceed to the end of file. 

Output 

  For every test case, print an integer on a single line, representing the maximum possible area that can 

be covered. 

Sample Input 

1 4
2 3
3 2
4 4 

Sample Output 

0
4
4
12