$($a$)(10\%)$ Find two trapping sets of the $(10,6)$ LDPC code from the null space

over GF$(2)$ of $H$ which are different from those given in Fig $11\mathrm{.}12.$

$($a$)(10\%)$ Find another two trapping sets of the $(10,6)$ LDPC code in

Example $11\mathrm{.}1$ which are different from those given in Fig $11\mathrm{.}15,$ one of size $4$

and the other of size $3.$

$H=\left[\begin{array}{cccccccccc}1& 1& 1& 1& 0& 0& 0& 0& 0& 0\\ 1& 0& 0& 0& 1& 1& 1& 0& 0& 0\\ 0& 1& 0& 0& 1& 0& 0& 1& 1& 0\\ 0& 0& 1& 0& 0& 1& 0& 1& 0& 1\\ 0& 0& 0& 1& 0& 0& 1& 0& 1& 1\end{array}\right].$

Figure $11\mathrm{.}15$ Two stopping sets of the $(10,6)$ LDPC code given in Example $11\mathrm{.}1.$