| st.min < a ⊦ st[a, d].min = st.min, st = ∅ |
st.keys.min < a, st.keys.min ∈ st ⊦ st[a, d].min = st.keys.min, st = ∅
Used simplifier rules: min-def: ⊦ st ≠ ∅ → st.min = st.keys.min;%Min-in: ⊦ st ≠ ∅ → st.min ∈ st;%Min-min: ⊦ a ∈ st → ¬ a < st.min;%inf: ⊦ a ∈ st → a ∈ st.keys;%Keys: ⊦ a ∈ st.keys ↔ a ∈ st;% ⊦ ¬ a < a; (s)