View Compilation Error

0_0_14737840_14152.cpp: In member function 'void max_match::init(int)':
0_0_14737840_14152.cpp:19:30: error: 'memset' was not declared in this scope
   memset(head,-1,sizeof(head));
                              ^
0_0_14737840_14152.cpp: In member function 'int max_match::solve()':
0_0_14737840_14152.cpp:48:30: error: 'memset' was not declared in this scope
   memset(left,-1,sizeof(left));
                              ^