View Compilation Error

0_0_32556430_16551.cpp: In function 'int bfs(int, bool)':
0_0_32556430_16551.cpp:29:31: error: 'memset' was not declared in this scope
     memset(vis, 0, sizeof(vis));
                               ^
0_0_32556430_16551.cpp: In function 'int main()':
0_0_32556430_16551.cpp:66:37: error: 'memset' was not declared in this scope
         memset(town, 0, sizeof(town));
                                     ^