View Compilation Error

0_0_20054613_24297.cpp: In function 'int main()':
0_0_20054613_24297.cpp:16:23: error: 'memset' was not declared in this scope
   memset(g,0,sizeof(g));
                       ^
0_0_20054613_24297.cpp: In function 'int MaxMatch()':
0_0_20054613_24297.cpp:38:27: error: 'memset' was not declared in this scope
  memset(cx,0xff,sizeof(cx));//初始化元素
                           ^