Compilare: main.cpp: In member function 'void bigNR::operator*=(int)': main.cpp:31:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<val.size();i++){ ~^~~~~~~~~~~ main.cpp: In member function 'void bigNR::operator+=(const bigNR&)': main.cpp:51:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<max(oth.val.size(),val.size());i++){ ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:52:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] t += (i < val.size() ? val[i] : 0) + (i < oth.val.size() ? oth.val[i] : 0); ~~^~~~~~~~~~~~ main.cpp:52:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] t += (i < val.size() ? val[i] : 0) + (i < oth.val.size() ? oth.val[i] : 0); ~~^~~~~~~~~~~~~~~~ main.cpp:53:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i >= val.size()) val.push_back(0); ~~^~~~~~~~~~~~~ main.cpp:58:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if (i >= val.size()) val.push_back(0); ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:80:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("indep.in","r",stdin); ^ main.cpp:81:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("indep.out","w",stdout); ^