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ZOJ Problem Set - 2028
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Time Limit: 2 Seconds      Memory Limit: 65536 KB

Wishingbone has a new house of which the floor needs to be coverd by ceramic tiles. A ceramic tile shapes like the letter 'L'. Now Wishingbone wants to know whether the floor can be fully coverd by sufficiently many tiles.

Figure 1 illustrates a tile. Figure 2 shows how the floor with size 2 * 4 be coverd by 2 tiles.

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 Figure 1       Figure 2


Input

Input consists of several cases, each occupies one line that contains 2 positive integers m and n, which describe the sizes of the floor.


Output


For each case, if the floor can be fully coverd by tiles output "Yes" in a line; else output the least spaces that can not be coverd.


Sample Input

1 3
2 3
2 4


Sample Output

3
2
Yes



Author: CHEN, Weichao
Source: ZOJ Monthly, November 2003
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