| st.keys ≠ ∅ ⊦ (st.keys ++ a).min = st.min, a = (st.keys ++ a).min, a < st.keys.min ∧ st.keys ≠ ∅ |
⊦ # st.keys = 0, st.keys = ∅, a = (st.keys ++ a).min, (st.keys ++ a).min = st.min, a < st.keys.min
Used simplifier rules: size-zero: ⊦ # s ≠ 0 → s ≠ ∅; (forward) from specification set-basic%size-zero-01: ⊦ s ≠ ∅ → # s ≠ 0; (forward) from specification set-basic