Agre-sara (movers in front): in both grāmas, all svaras other than ṣaḍja and madhyama play this role
Body (pseudocode)
DEFINE agre_sara(svara s, grama g):
IF s IN {shadja, madhyama}: RETURN 'not_agresara' // these are leaders
ELSE: RETURN 'agresara' // movers in front, follower role