Time Limit

1s

Memory Limit

32768KB

Judge Program

Standard

Ratio(Solve/Submit)

30.65%(19/62)

Description:

Tom's Meadow

Tom has a meadow in his garden. He divides it into N * M squares. Initially all the squares were covered with grass. He mowed down the grass on some of the squares and thinks the meadow is beautiful if and only if

- Not all squares are covered with grass.
- No two mowed squares are adjacent.

Input:

The input contains multiple test cases!

Each test case starts with a line containing two integers N, M (1 <= N, M <= 10) separated by a space. There follows the description of Tom's Meadow. There're N lines each consisting of M integers separated by a space. 0(zero) means the corresponding position of the meadow is mowed and 1(one) means the square is covered by grass.

A line with N = 0 and M = 0 signals the end of the input, which should not be processed

Output:

One line for each test case.

Output "Yes" (without quotations) if the meadow is beautiful, otherwise "No"(without quotations).

Sample Input:

2 2 1 0 0 1 2 2 1 1 0 0 2 3 1 1 1 1 1 1 0 0

Sample Output:

Yes No No

Submit