Compilare: user.cpp: In function ‘int main()’: user.cpp:24:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] loc[pi1].push_back(i); ^ user.cpp:25:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] loc[pi2].push_back(26 + i); ^ user.cpp:34:22: warning: array subscript has type ‘char’ [-Wchar-subscripts] cerr << loc[c].size() << "\n"; ^ user.cpp:35:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] int loc1 = loc[c][0], loc2 = loc[c][1]; ^ user.cpp:35:43: warning: array subscript has type ‘char’ [-Wchar-subscripts] int loc1 = loc[c][0], loc2 = loc[c][1]; ^