Compilare: user.cpp: In function ‘int update(int, int)’: user.cpp:13:37: warning: suggest parentheses around arithmetic in operand of ‘^’ [-Wparentheses] for (; x <= n; x += x ^ (x - 1) & x) ^ user.cpp:16:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int query(int)’: user.cpp:21:32: warning: suggest parentheses around arithmetic in operand of ‘^’ [-Wparentheses] for (; x; x -= x ^ (x - 1) & x) ^ user.cpp: In function ‘int main()’: user.cpp:65:14: warning: unused variable ‘i’ [-Wunused-variable] for (int i = it; it; printf("%d ", b[it--])); ^ user.cpp:30:34: 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:31:36: 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:33:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:36:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^