Compilare: main.cpp: In function 'int main()': main.cpp:16:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < a.size(); i++) ~~^~~~~~~~~~ main.cpp:21:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < b.size(); i++) ~~^~~~~~~~~~ main.cpp:30:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = a.size(); i < b.size(); i++) ~~^~~~~~~~~~