/in/foo.cc: In function 'bool Bfs()':
/in/foo.cc:20:27: error: 'memset' was not declared in this scope
  memset(vis, 0, sizeof vis);
                           ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:63:19: warning: format '%lld' expects argument of type 'long long int*', but argument 2 has type 'int*' [-Wformat=]
    scanf("%lld",&z);
                   ^
/in/foo.cc:68:28: warning: format '%lld' expects argument of type 'long long int*', but argument 4 has type 'int*' [-Wformat=]
   scanf("%d%d%lld",&x,&y,&z);
                            ^