The components of pure shear strain in a sheared material are given in the matrix form:

\(ε = \begin{bmatrix} 1 & 1 \\\ 1 & -1 \end{bmatrix} \)

Here, Trace (ε) = 0. Given, P = Trace (ε⁸) and Q = Trace (ε¹¹).

The numerical value of (P + Q) is ________. (in integer)