Compilare: user.cpp: In function ‘void add(int)’: user.cpp:29:14: warning: unused variable ‘i’ [-Wunused-variable] for (int i = x; x <= n; x += lsb(x)) ^ user.cpp: In function ‘int query(int)’: user.cpp:36:11: warning: statement has no effect [-Wunused-value] for (x; x >= 1; x -= lsb(x)) ^ user.cpp: In function ‘int main()’: user.cpp:43:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bignumber.in", "r", stdin); ^ user.cpp:44:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("bignumber.out", "w", stdout); ^ user.cpp:45:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &n, &m); ^ user.cpp:46:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", s + 1); ^