Compilare: user.cpp: In function ‘int main()’: user.cpp:50:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<s.size();i++) ^ user.cpp:68:14: warning: array subscript has type ‘char’ [-Wchar-subscripts] lit[l]=1-lit[l]; ^ user.cpp:68:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] lit[l]=1-lit[l]; ^ user.cpp:83:37: warning: array subscript has type ‘char’ [-Wchar-subscripts] S.push(lit[str[j][0]]); ^