Trying efficient sql

Question

I have a table with 3 columns
f1 c1 val
1 3 E
1 3 W
1 3 E
3 4 E
4 5 W
I am trying to write a query like find DISTINCT values of "val" field for "f1" and "C1" fields. If it returns both "E" and "W"
just display "BOTH" or if it "E" write EVENT or it it is "W" just display "WORD"
For Example, for 1 and 3 values ---> BOTH
3 and 4 values ---> EVENT
4 and 5 values ----> WORD
You help is appreciated:

Answer 1

drop table t purge
create table t
f1 number,
c1 number,
val char(1)
insert into t values (1,3,'E');
insert into t values (1,3,'W');
insert into t values (1,3,'E');
insert into t values (3,4,'E');
insert into t values (4,5,'W');
commit;
select *
from t;
F1 C1 VAL
1 3 E
1 3 W
1 3 E
3 4 E
4 5 W
5 rows selected
select f1,c1,
decode(cnte,0,decode(cntw,0,'None','Word'),decode(cntw,0,'EVENT','BOTH'))dcd
from
(select f1,c1,count(decode(val,'E','E'))cnte,
count(decode(val,'W','W'))cntw
from t
group by f1,c1);
F1 C1 DCD
4 5 Word
1 3 BOTH
3 4 EVENT
3 rows selected