Compilare: user.cpp: In function ‘int main()’: user.cpp:170:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int j = nr[i]; j < lst[i].size(); j ++ ) { ^ user.cpp:171:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int k = 0; k < lst[fth[i]].size(); k ++ ) { ^ user.cpp: In member function ‘char InParser::read_ch()’: user.cpp:18:38: 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); ^