Compilare: user.cpp: In member function ‘bool Buffer::isDigit(char)’: user.cpp:34:22: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] return c >= '0' & c <= '9'; ^ user.cpp: In function ‘int main()’: user.cpp:73:35: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings] Buffer cin("dtcsu.in",1024*256); ^ user.cpp:74:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("dtcsu.out","w",stdout); ^ user.cpp: In constructor ‘Buffer::Buffer(char*, long int)’: user.cpp:14:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(fileName,"r",stdin); ^ user.cpp: In member function ‘void Buffer::reFill()’: user.cpp:37:43: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(&Buff[0],1,maxBuf,stdin); pos = 0; ^