Compilare: user.cpp: In member function ‘bool Buffer::isDigit(char)’: user.cpp:45:22: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] return c >= '0' & c <= '9'; ^ user.cpp: In function ‘int main()’: user.cpp:183:33: warning: deprecated conversion from string constant to ‘char*’ [-Wwrite-strings] Buffer fin("ksecv4.in",1<<20); ^ user.cpp:184:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ksecv4.out","w",stdout); ^ user.cpp: In constructor ‘Buffer::Buffer(char*, long int)’: user.cpp:13:40: 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:48:43: 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; ^