View Compilation Error

0_0_30548608_1856.cpp: In function 'int bfs(int, int&)':
0_0_30548608_1856.cpp:80:24: error: 'memset' was not declared in this scope
  memset(v, 0, sizeof(v));
                        ^
0_0_30548608_1856.cpp: In function 'int main()':
0_0_30548608_1856.cpp:121:28: error: 'memset' was not declared in this scope
   memset(low,0, sizeof(low));
                            ^