| buf0 + buf1 = buf2 + buf3, # buf2 < # buf0, is-encoded(a, buf0) ⊦ is-encoded(b, buf2) ↔ # buf0 = # buf2 ∧ a = b |
⊦ is-encoded(a, buf) ∧ n ≤ # buf → (is-encoded(b, subarray(buf, 0, n)) ↔ b = a ∧ n = # buf)
buf0 + buf1 = buf2 + buf3, # buf2 < # buf0, is-encoded(a, buf0), is-encoded(a, buf0) ∧ # buf2 ≤ # buf0 → (is-encoded(b, subarray(buf0, 0, # buf2)) ↔ b = a ∧ # buf2 = # buf0) ⊦ is-encoded(b, buf2) ↔ # buf0 = # buf2 ∧ a = b
Used terms: a, buf0, # buf2, b