Find Out greatest Of Three Number's In PL/SQL

declare
a number(10);
b number(10);
c number(10);
begin
a:=&a;
b:=&b;
c:=&c;
if(a>b)and(a>c) then
dbms_output.put_line('a is greater');
elsif(b>c) then
dbms_output.put_line('b is greater');
else
dbms_output.put_line('c is greater');
end if;
end;
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