thys/MyFirst.thy
changeset 17 a5427713eef4
parent 16 a92c10af61bd
child 19 66c9c06c0f0e
equal deleted inserted replaced
16:a92c10af61bd 17:a5427713eef4
    91 
    91 
    92 fun mull :: "nat \<Rightarrow> nat \<Rightarrow> nat" where
    92 fun mull :: "nat \<Rightarrow> nat \<Rightarrow> nat" where
    93 "mull 0 0 = 0" |
    93 "mull 0 0 = 0" |
    94 "mull m 0 = 0" |
    94 "mull m 0 = 0" |
    95 (**"mull m 1 = m" | **)
    95 (**"mull m 1 = m" | **)
    96 "mull m n = m*n" 
    96 (**"mull m (1::nat) = m" | **)
       
    97 (**"mull m (suc(0)) = m" | **)
       
    98 "mull m n = mull m (n-(1::nat))" 
    97 
    99 
       
   100 (**Define a function that counts the
       
   101 number of occurrences of an element in a list **)
    98 (**
   102 (**
    99 fun count :: "'a\<Rightarrow>'a list\<Rightarrow>nat" where
   103 fun count :: "'a\<Rightarrow>'a list\<Rightarrow>nat" where
   100 "count  "
   104 "count  "
   101 **)
   105 **)
   102 
   106