Compilare: main.cpp: In function 'int main()': main.cpp:14:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<aux.size();i++) ~^~~~~~~~~~~ main.cpp:22:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<s.length();i++) ~^~~~~~~~~~~ main.cpp:30:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(k<s.length() && s[k]==s[2*i-k]) ~^~~~~~~~~~~