Compilare: main.cpp: In function 'void euler()': main.cpp:17:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[w].size(); ++i) ~~^~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:42:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sol.size() - 1; ++i) g << sol[i] << ' '; ~~^~~~~~~~~~~~~~~~