Array ( [0] => Array ( [title] => L6AR [link] => https://www.youtube.com/embed/GI8GPyo7hNs ) [1] => Array ( [title] => L6BR [link] => https://www.youtube.com/embed/MKjRPNnwu3A ) [2] => Array ( [title] => L6CR [link] => https://www.youtube.com/embed/UF9dV0m3_wQ ) ) 國立清華大學開放式課程OpenCourseWare(NTHU, OCW) - 第6講 Ch.2 Symmetric-key encryption (3).Ch.3 Algebra & number theory basics (1)