create or replace procedure pr_half_find(in_num in number,in_arr in varchar2)
is
type arr_num is table of number index by binary_integer;
my_arr_num arr_num;
n_arr_index number(10):=0;
n_upper_bound number(10);
n_lower_bound number(10);
n_cur_index number(10);
begin
for i in (select my_date from (
select regexp_substr(in_arr,'[^,]+',1,rownum) my_date from dual
connect by rownum<= length(in_arr) - length(replace(in_arr,',',''))+1
)
order by to_number(my_date))
loop
n_arr_index := n_arr_index+1;
my_arr_num(n_arr_index) := i.my_date;
dbms_output.put_line(n_arr_index||' '||my_arr_num(n_arr_index));
end loop;
n_upper_bound := 1;
n_lower_bound := n_arr_index;
if in_arr is not null then
while true
loop
n_cur_index := floor((n_upper_bound + n_lower_bound)/2);
if my_arr_num(n_cur_index) = in_num then
dbms_output.put_line('在第'||n_cur_index||'位');
exit;
end if;
if n_upper_bound>=n_lower_bound then
exit;
end if;
if my_arr_num(n_cur_index) > in_num then
n_lower_bound := n_cur_index;
else
n_upper_bound := n_cur_index+1;
end if;
end loop;
end if;
end;