Traverse to Parent for the given child in SQL

Hi,

I have a table with below structure and data.

{Code}

CREATE TABLE A

(

   CHILD_ID      NUMBER,

   EVALUE        VARCHAR2(100 CHAR),

   PARENT_ID     NUMBER

)

INSERT INTO A  VALUES ( 3803783, 'BLADE', 3803772);

INSERT INTO A  VALUES ( 3803772, 'PE', 3803767);

INSERT INTO A  VALUES ( 3803767, 'MEC', 0);

INSERT INTO A  VALUES ( 3847134, 'DE', 3803767);

INSERT INTO A  VALUES ( 3803767, 'MEC', 0);

{code}

I want output string as 'MEC || PE || BLADE' if I start with Child 3803783, similarly I should get 'MEC || DE' if I start with child 3847134

Could you please help me with SQL query.

Regards,

Laxman