Input: Executive file
Output: Opcode sequence
   = ; // Get all executive files;
for in;
= ; // Open the corresponding IDA pro decompiled file;
for in; // Read in line;
= t(“  ”); // Cut the line into phrases by space character;
for    in  ;
//To judge each phrase, it requires to meet the following two points at the same time:
The current word belongs to opcode set opcode_set;
The last three words are not duplicated opcodes.
if    in    and   =   and   =
= ;
= ;
;
(11)end if
(12) end for
(13)end for
(14) end for
Algorithm 1: Opcode sequence extraction algorithm for executive files.