We have a $3 \times 3$ grid. A number $c_{i, j}$ is written in the square $(i, j)$, where $(i, j)$ denotes the square at the $i$\-th row from the top and the $j$\-th column from the left.
According to Takahashi, there are six integers $a_1, a_2, a_3, b_1, b_2, b_3$ whose values are fixed, and the number written in the square $(i, j)$ is equal to $a_i + b_j$.
Determine if he is correct.
## Constraints
* $c_{i, j} \ (1 \leq i \leq 3, 1 \leq j \leq 3)$ is an integer between $0$ and $100$ (inclusive).
## Input
Input is given from Standard Input in the following format:
$c_{1,1}$ $c_{1,2}$ $c_{1,3}$
$c_{2,1}$ $c_{2,2}$ $c_{2,3}$
$c_{3,1}$ $c_{3,2}$ $c_{3,3}$
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