min(m, n) < n0, n < n0, n ≤ m ⊦ n = min(min(m, n), n0), n0 = 0
n < n0, n ≤ m ⊦ min(m, n) < n0, n = min(min(m, n), n0), n0 = 0
Used formulas: min(m, n) < n0