| m < BRANCH_SIZE, n < BRANCH_SIZE, m + nused ≤ BRANCH_SIZE, ∃ n0. m + n0 = n ⊦ save(load(save(zbrar, m, nused), m, nused), m, nused)[n] = save(zbrar, m, nused)[n] |
m + n0 < BRANCH_SIZE, m < BRANCH_SIZE, m + nused ≤ BRANCH_SIZE ⊦ save(load(save(zbrar, m, nused), m, nused), m, nused)[m + n0] = save(zbrar, m, nused)[m + n0]