View Compilation Error

0_0_23599668_20827.cpp:13:13: error: macro "mem" passed 2 arguments, but takes just 1
   mem(vis, 0);
             ^
0_0_23599668_20827.cpp: In function 'void build()':
0_0_23599668_20827.cpp:13:3: error: 'mem' was not declared in this scope
   mem(vis, 0);
   ^