Previously, there has been no report on implementation effort to integrate LDPC encoder and decoder into a single hardware. In this paper, we propose a simple yet low complex systematic LDPC encoding method for class of quasi-cyclic low-density parity-check (QC-LDPC) codes to let LDPC encoder acquire an interchangeable structure, exploited in the decoder. With the proposed encoding scheme, implementation of the proposed encoder becomes much more hardware efficient than having a separate hardware due to LDPC encoder and decoder resource sharing. Moreover, the overall computational complexity of the proposed encoding scheme is lower than the well-known Richardson's efficient encoding scheme (A.T.J. Richardson and R.L. Urbanke, 2001).