Compilare: user.cpp: In function ‘int main()’: user.cpp:64:10: warning: unused variable ‘enter’ [-Wunused-variable] char enter,direction; ^ user.cpp: In function ‘int GetInt()’: user.cpp:22:48: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^ user.cpp:28:48: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^ user.cpp: In function ‘char GetChar()’: user.cpp:37:48: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^ user.cpp:42:48: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf, 1, MaxB, stdin), Ptr = 0; ^ user.cpp: In function ‘int main()’: user.cpp:61:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zc.in","r",stdin); ^ user.cpp:62:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zc.out","w",stdout); ^ user.cpp:65:28: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(Buf,1,MaxB,stdin); ^ user.cpp:108:22: warning: ‘add’ may be used uninitialized in this function [-Wmaybe-uninitialized] answer=answer+add-subtract; ^ user.cpp:108:35: warning: ‘subtract’ may be used uninitialized in this function [-Wmaybe-uninitialized] answer=answer+add-subtract; ^