Compile INVALIDS

How to find the Invalid Objects?
select count(*) from DBA_OBJECTS where status='INVALID';
select owner,object_type,count(*) from dba_objects where status='INVALID' group by owner,object_type;

Compile Invalid Objects:
cd $ORACLE_HOME/rdbms/admin/utlrp.sql
Connect sqlplus "as sysdba"
sql>@utlrp.sql

This sql compile the All invalid Objects