View Compilation Error

0_0_22249901_13917.cpp: In function 'int BFS(int, int, std::map<int, std::pair<int, int> >&, std::map<int, std::pair<int, int> >&, std::map<std::pair<int, int>, int>&, int)':
0_0_22249901_13917.cpp:36:56: error: 'memset' was not declared in this scope
     memset(v, 0, sizeof(int)*((1<< (totalslots + 4))-1));
                                                        ^