I have two natural number lists l1 & l2. I am finding match element of l1 in l2 , in case it is found then remove it from l2 and add it infront of l2 else empty list.

l1=[2,3,4] l2=[5,3,6,2,8,4]

reult: 4,3,2,5,6,8

```
Fixpoint find (l1 l2: list nat ) : list nat :=
match l1,l2 with
| nil , nil => nil
| [], a2::t => []
| a1::t , [] => []
| a1::t1,a2::t2=> if ( eq a1 a2) then (remove a1 t2) a1 ::t2 find t1 t2 else []
```

Last updated: Oct 04 2023 at 20:01 UTC