On 5/06/2018, at 23:08, سیدمهدی سیدحسینی <seyyedm...@gmail.com> wrote:hello , i try to solve a Practice (append it) and find a resolve for it (append it).
but i don't understand what happen in .
Please describe the code for me .
what is op() in line 22 and 23 and what do this tow lines ?
and how test and how use query for test in run ?
i know what happen in line 32 to 39 .
what is d() in line 41 to 51 ?
and what do this lines?