Compilare: user.cpp: In function ‘int get_int()’: user.cpp:39:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] for(; !isDigit[*head]; ++head); ^ user.cpp:41:25: warning: array subscript has type ‘char’ [-Wchar-subscripts] for(; isDigit[*head]; ++head) ^ user.cpp: In function ‘int main()’: user.cpp:142:3: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation] for (register int i = 1; i <= N; ++i) ^~~ user.cpp:144:5: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘for’ fwrite(buffer, 1, writeHead - buffer, stdout); ^~~~~~ user.cpp: At global scope: user.cpp:48:37: warning: always_inline function might not be inlinable [-Wattributes] __attribute__((always_inline)) void put_int(int x) ^~~~~~~ user.cpp:35:36: warning: always_inline function might not be inlinable [-Wattributes] __attribute__((always_inline)) int get_int() ^~~~~~~ user.cpp: In function ‘int main()’: user.cpp:124:30: 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:125:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(OuFile, "w", stdout); ^