Compilare: user.cpp: In function ‘int factor()’: user.cpp:83:24: warning: array subscript has type ‘char’ [-Wchar-subscripts] r = !v[s[p]]; ^ user.cpp:85:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] r = v[s[p]]; ^ user.cpp: In function ‘int main()’: user.cpp:151:6: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] s[j] = NULL; ^ user.cpp:157:11: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(v[c] == 0) ^ user.cpp:158:12: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[c] = 1; ^ user.cpp:160:12: warning: array subscript has type ‘char’ [-Wchar-subscripts] v[c] = 0; ^ user.cpp: In function ‘int factor()’: user.cpp:90:1: warning: control reaches end of non-void function [-Wreturn-type] } ^