Compilare: In file included from /usr/include/c++/4.8/cassert:43:0, from user.cpp:3: user.cpp: In function ‘int bs_first_greater_or_equal(std::vector<int>&, int, int, int)’: user.cpp:23:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(l >= 0 && r < v.size() + 1); ^ user.cpp:26:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] assert(m >= 0 && m < v.size()); //m points to an actual element inside the vector ^ user.cpp: In function ‘int main()’: user.cpp:61:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(IA_PROB".in", "r", stdin); ^ user.cpp:62:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(IA_PROB".out", "w", stdout); ^ user.cpp:65:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:71:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ user.cpp:76:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &m); ^ user.cpp:81:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &op, &x); ^