数据结构中关于十字链表的实现，十字链表可以很好的对稀疏矩阵进行效率很高的存储和计算。比如在通信纠错编码的ldpc编译码中就要用到这种数据结构-data structure on the realization of Chain Cross, Cross List can be good for sparse matrix highly efficient storage and computing. For example, in communications-correction coding

a)Refer to the LDPC presentation slides provided, and use the input data provided below to decode the codeword Repeat a) with new matrix H, codeword and σ^2 given below-a) Refer to the LDPC presentation slides provided, and use the input data provi

生成一个规则LDPC码的教研矩阵H,其行数(越大越好)为列数的一半-Generate a regular LDPC code research matrix H, the adults number (bigger is better) for half the number of columns