A custom decoding algorithm is introduced, in connection with a corresponding decoding structure, to resolve many complexity and large memory requirements of known decoders. A system. A variable node forms a confidence vector of four components, one component for each state of a memory cell, and passes the current primary component (e.g., the largest) to one or more check nodes. The check nodes calculate a temporary component and corresponding index based on all components received from the variable nodes, which they pass back to the respective variable nodes. The variable node updates the confidence vector based on the temporary nodes received from respective check nodes, and determines the correct state for corresponding memory cell based on which component in the confidence vector is currently the primary component.