binrel_binop.lean:1:8-1:11: warning: declaration uses 'sorry'
ex1 : ∀ (a : Int) (b c : Nat), a = Int.ofNat b - Int.ofNat c
binrel_binop.lean:5:8-5:11: warning: declaration uses 'sorry'
ex2 : ∀ (a : Int) (b c : Nat), a = Int.ofNat b - Int.ofNat c
binrel_binop.lean:9:8-9:11: warning: declaration uses 'sorry'
ex3 : ∀ (a : Int) (b c : Nat), a = Int.ofNat (b - c)