Compilare: user.cpp: In function ‘void update(int, int)’: user.cpp:147:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = k; i<fn.size(); i+=i&-i) ~^~~~~~~~~~ user.cpp: In function ‘int main()’: user.cpp:208:17: warning: unused variable ‘x’ [-Wunused-variable] int x = get<0>(t), p = get<1>(t); ^ user.cpp: In member function ‘char InParser::read_ch()’: user.cpp:14:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^