Building relationship among a list of codes

Hi
I have a dataset consisting of two csv files.

The first csv is a list of codes and their description. Example:
1, A
2, B
3, C

The second CSV, contains a list of related codes. Example
1, 2
1, 1
2, 3

The code may be related to themselves or to other codes. Some of the codes may not have any relations.

I have loaded the first csv and created nodes for the code and description
How can I load the second csv to create the relationships between the nodes ?

Thanks

Br
Praveen

I am able to get the relationship with the below queries:
LOAD CSV from 'file:///AllCodes.csv' as row
FIELDTERMINATOR ';'
with toInteger(row[0]) as codeID, row[1] as CodeDescription
MERGE (m:CodeList {codeID: codeID, CodeDescription: CodeDescription});

LOAD CSV from 'file:///CodeRelations.csv' as row
FIELDTERMINATOR ';'
with toInteger(row[0]) as leftID, toInteger(row[2]) as rightID
MATCH (code1), (code2)
WHERE code1.codeID = leftID AND code2.codeID = rightID
CREATE (code1)-[:PT]->(code2);

If there is any better/faster way to do it. Please do let me know.

Thanks