% use \setcounter{MaxMatrixCols}{20} in preamble
\begin{bmatrix}
1 & -1 & 1 & 1 & 0 &  0 & 0 &  0 & 0 &  0 & 0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 \\
0 &  0 & 0 & 0 & 1 & -1 & 0 &  0 & 0 &  0 & 0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 \\
0 &  0 & 0 & 0 & 0 &  0 & 1 & -1 & 0 &  0 & 0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 \\
0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 1 & -1 & 0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 \\
0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 & 1 & -1 & 1 & 1 & 0 &  0 & 0 &  0 & 0 &  0 \\
0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 & 0 &  0 & 0 & 0 & 1 & -1 & 0 &  0 & 0 &  0 \\
0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 & 0 &  0 & 0 & 0 & 0 &  0 & 1 & -1 & 0 &  0 \\
0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 0 &  0 & 0 &  0 & 0 & 0 & 0 &  0 & 0 &  0 & 1 & -1
\end{bmatrix}