Compilare: user.cpp: In function ‘void update(int, int)’: user.cpp:12:33: warning: suggest parentheses around arithmetic in operand of ‘^’ [-Wparentheses] for (; x <= N; x += x^(x-1) & x) ~~~~~~^~~ user.cpp: In function ‘int query(int)’: user.cpp:21:28: warning: suggest parentheses around arithmetic in operand of ‘^’ [-Wparentheses] for (; x; x -= x^(x-1) & x) ~~~~~~^~~ user.cpp: In function ‘int main()’: user.cpp:31:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("scmax.in", "r", stdin); ^ user.cpp:32:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("scmax.out", "w", stdout); ^ user.cpp:34:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &N); ^ user.cpp:37:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^