Consider the following matrix. \(\begin{pmatrix} 0 & 1 & 1 & 1\\ 1& 0& 1 & 1\\…

Consider the following matrix.

$\begin{pmatrix} 0 & 1 & 1 & 1\\ 1& 0& 1 & 1\\ 1& 1 & 0 & 1 \\1 & 1 & 1 & 0 \end{pmatrix}$

The largest eigenvalue of the above matrix is __________.