/in/foo.cc: In function 'int lca(int, int)':
/in/foo.cc:59:28: warning: array subscript has type 'char' [-Wchar-subscripts]
   x=fa[x][lg[dep[x]-dep[y]]];
                            ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:71:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
   if(i>=k) j++,k<<=1;lg[i]=j;
   ^~
/in/foo.cc:71:22: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
   if(i>=k) j++,k<<=1;lg[i]=j;
                      ^~