View Compilation Error

0_0_19153074_20272.cpp: In function 'int main()':
0_0_19153074_20272.cpp:4:29: error: 'memset' was not declared in this scope
 #define qk(x) memset(x,0,MAX)
                             ^
0_0_19153074_20272.cpp:14:3: note: in expansion of macro 'qk'
   qk(n1);
   ^