View Compilation Error

0_0_24931539_2690.cpp: In function 'int dij(int)':
0_0_24931539_2690.cpp:12:36: error: 'memset' was not declared in this scope
  memset(visit, false, sizeof(visit));
                                    ^
0_0_24931539_2690.cpp: In function 'int main()':
0_0_24931539_2690.cpp:51:37: error: 'memset' was not declared in this scope
   memset(visit, false, sizeof(visit));
                                     ^