Plain meaning
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A PDA-like addressing scheme for compressed accounts in the ZK Compression system. Compressed PDAs provide deterministic, program-derived addressing for compressed account leaves, enabling programs to locate and reference compressed state using seeds and program IDs similar to regular PDAs. The address is derived from seeds and stored as part of the compressed account's leaf data in the Merkle tree, with the Light System Program enforcing uniqueness through an address queue and nullifier mechanism.