def main(input):
    output = []
    for row in input:
        region = row["region"].strip().upper()
        known = region in ("EMEA", "AMER", "APAC")
        segment = "ENTERPRISE" if int(row["employees"]) >= 500 else "SMB"
        output.append(dict(row, assigned_team=region + "_" + segment if known else "UNASSIGNED",
            routing_status="assigned" if known else "review",
            routing_reason="region + employee threshold 500" if known else "unknown region"))
    return output