Compilare: main.cpp: In function 'int main()': main.cpp:22:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<s.size();i++) fr[s[i]]++; ~^~~~~~~~~ main.cpp:22:36: warning: array subscript has type 'char' [-Wchar-subscripts] for(i=0;i<s.size();i++) fr[s[i]]++; ^ main.cpp:26:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<v.size();i++){ ~^~~~~~~~~ main.cpp:28:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<s.size();j++){ ~^~~~~~~~~ main.cpp:30:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j==s.size()-1){ ch=s[j-1]; ch1=s[0]; } ~^~~~~~~~~~~~