Assign value based on time

Hello buddies,

I have a SAP Business Intelligence report question.

I want to create a variable like this.

IN       CN       TIME     VARIABLE

1          101      00:52    P

1          102      00:58    C

1          103      01:25    C

2          104      00:58    C

2          105      00:51    P

I. E.  The variable will assign P value to the first time under lN