View Compilation Error

0_0_17715213_29659.cpp: In function 'int MaxMatch()':
0_0_17715213_29659.cpp:30:28: error: 'memset' was not declared in this scope
     memset(cx,-1,sizeof(cx));//从1匹配开始增广，将cx，cy各元素初始化为-1.
                            ^
0_0_17715213_29659.cpp: In function 'int main()':
0_0_17715213_29659.cpp:48:33: error: 'memset' was not declared in this scope
         memset(map,0,sizeof(map));
                                 ^