Compilare: user.cpp: In member function ‘void FenwickTree::add(int, int)’: user.cpp:19:36: warning: suggest parentheses around ‘+’ in operand of ‘&’ [-Wparentheses] for (; x < size(); x += (x + 1 & -x - 1)) ^ user.cpp: In member function ‘int FenwickTree::query(int)’: user.cpp:25:31: warning: suggest parentheses around ‘+’ in operand of ‘&’ [-Wparentheses] for (; x > 0; x -= (x + 1 & -x - 1)) ^