java recursion test if arraylist are equal -

i have code make more efficient recursion. trouble don't know start. code compares 2 arraylists , b see if equal. assume sizes of both arrays equal.

the code is

public boolean isequal(a b) {     boolean answer = false;     if (lessthanorequalto(b) == true);     (int = 0; < dlist.size(); i++) {         if (dlist.get(i) == b.dlist.get(i)) answer = true;         else answer = false;     }     return answer; } 

i have written

public boolean isequalrecursion(a b) {     if dlist.size() == 0;     return false(); } else {  } 

i know stopping case 0 when size 0 nothing happens. have no idea write next

any appreciated

thanks

i think pretty start you. looks through elements, assuming array, , checks if equal in size.

public boolean isequal(arraylist<?> a, arraylist<?> b) {     if (a.size() != b.size())         return false;      (int = 0; < a.size(); i++) {         if (!isequal((arraylist<?>)a.get(i), (arraylist<?>)b.get(i))) {             return false;         }     }     return true; } 

now couple of things consider:

• this assumes content of a(and b) must arraylist @ line (arraylist<?>)a.get(i) if our arraylist contains else, integer?

• what if our array lists contain null item?

• what if pass in 2 null arraylists? (or one?)

i'm not sure point of function lessthanorequalto(b) part of question or did write down wrong?

also dlist?