Compilare: user.cpp: In function ‘bool check(int)’: user.cpp:79:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (pas = 0; pas < best.size(); pas++) { ^ user.cpp:73:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, pas, wh, need, wh2; ^ user.cpp: In function ‘bool recon(int)’: user.cpp:114:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (pas = 0; pas < best.size(); pas++) { ^ user.cpp:108:12: warning: unused variable ‘j’ [-Wunused-variable] int i, j, pas, wh, need, wh2; ^ user.cpp: In function ‘int main()’: user.cpp:191:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j < sol[i].size(); j++) ^ user.cpp:151:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("danger.out", "w", stdout); ^ user.cpp: In constructor ‘Buffer::Buffer(std::string, int)’: user.cpp:20:46: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(name.c_str(), "r", stdin); ^ user.cpp: In member function ‘void Buffer::refill()’: user.cpp:52:43: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(&data[0], 1, dim, stdin); ^