Compilare: main.cpp: In function 'int main()': main.cpp:24:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<a.size(); i++) ~^~~~~~~~~ main.cpp:37:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] { while(i <= n && nr < w.size()) ~~~^~~~~~~~~~ main.cpp:44:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(nr == w.size()) ~~~^~~~~~~~~~~