Compilare: user.cpp: In function ‘int main()’: user.cpp:15:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<s.size();i++) ^ user.cpp:17:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] val[s[i]]=i; ^ user.cpp:28:28: warning: array subscript has type ‘char’ [-Wchar-subscripts] nr=val[x[j]]*putere; ^