View Compilation Error

0_0_24931544_30005.cpp: In function 'int dij(int)':
0_0_24931544_30005.cpp:13:36: error: 'memset' was not declared in this scope
  memset(visit, false, sizeof(visit));
                                    ^
0_0_24931544_30005.cpp: In function 'int main()':
0_0_24931544_30005.cpp:52:37: error: 'memset' was not declared in this scope
   memset(visit, false, sizeof(visit));
                                     ^