Compilare: user.cpp: In function ‘int organize()’: user.cpp:41:36: warning: array subscript has type ‘char’ [-Wchar-subscripts] const int next = pos[lst[i]].back(); ^ user.cpp:42:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] pos[lst[i]].pop_back(); ^ user.cpp: In function ‘int operations()’: user.cpp:59:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] pos[fst[i]].push_back(i); ^ user.cpp:61:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] ap[fst[i]]++; ^ user.cpp:62:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] ap[lst[i]]--; ^ user.cpp:68:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] if( ap[it] != 0 ) ^