View Compilation Error

0_0_24396984_13156.cpp: In member function 'void Graph::init(int)':
0_0_24396984_13156.cpp:19:36: error: 'memset' was not declared in this scope
         memset(head,-1,sizeof(head));    
                                    ^
0_0_24396984_13156.cpp: In member function 'int Graph::SAP(int, int)':
0_0_24396984_13156.cpp:30:33: error: 'memset' was not declared in this scope
         memset(dis,0,sizeof(dis));  
                                 ^
0_0_24396984_13156.cpp: In function 'int main()':
0_0_24396984_13156.cpp:113:23: error: 'memset' was not declared in this scope
   memset(h,0,sizeof(h));
                       ^