ONodes OHuffmanCode MentropyCode Vsibling VHUFFM-Like Ventropy-Like Ris_entropyCode-Like Ris_HuffmanCode-Like Ris_constructingHuffman OInitial-Trees OExtSOURCE OMakeTree OSearchMin OVtree OVrootr OVrootl OMaxVl VValueMin Ris_MinValueTree_of OBinFinTrees OBoolBinFinTrees OLeavesSet