Compilare: main.cpp: In function 'std::vector<int> operator+(const std::vector<int>&, const std::vector<int>&)': main.cpp:13:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < a.size() && i < b.size(); i++, t = t/10) ~~^~~~~~~~~~ main.cpp:13:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < a.size() && i < b.size(); i++, t = t/10) ~~^~~~~~~~~~ main.cpp:18:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = b.size(); i < a.size(); i++, t = t/10) ~~^~~~~~~~~~ main.cpp:23:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = a.size(); i < b.size(); i++, t = t/10) ~~^~~~~~~~~~ main.cpp: In function 'std::vector<int> operator*(const std::vector<int>&, const int&)': main.cpp:37:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i<a.size(); i++, t = t/10) ~^~~~~~~~~ main.cpp: In function 'std::vector<int> operator*(const std::vector<int>&, const std::vector<int>&)': main.cpp:56:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i<a.size(); i++) ~^~~~~~~~~ main.cpp:57:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0; j<b.size(); j++) ~^~~~~~~~~ main.cpp:59:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (t = 0, i = 0; i < c.size(); i++, t = t/10) ~~^~~~~~~~~~