Compilare: user.cpp: In function ‘int nextInt()’: user.cpp:40:24: warning: array subscript has type ‘char’ [-Wchar-subscripts] for (; !isDigit[*head]; ++head); ^ user.cpp:41:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] for (; isDigit[*head]; ++head) ^ user.cpp: In function ‘int main()’: user.cpp:97:33: warning: unused variable ‘b’ [-Wunused-variable] register int a = nextInt(), b = nextInt(); ^ user.cpp:92:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(InFile, "r", stdin); ^ user.cpp:93:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(OuFile, "w", stdout); ^