View Compilation Error

0_0_37711316_13713.cpp: In function 'int main()':
0_0_37711316_13713.cpp:9:22: error: 'size' was not declared in this scope
   memset(a, 0, size(a));
                      ^
0_0_37711316_13713.cpp:9:23: error: 'memset' was not declared in this scope
   memset(a, 0, size(a));
                       ^