Compilare: main.cpp:15:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] main() ^ main.cpp: In function 'int main()': main.cpp:45:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<act.size();i++) ~^~~~~~~~~~~ main.cpp:47:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<v[act[i]].size();j++) ~^~~~~~~~~~~~~~~~~