Compilare: user.cpp: In function ‘int main()’: user.cpp:50:13: warning: unused variable ‘y’ [-Wunused-variable] int y; ^ user.cpp:57:28: warning: suggest parentheses around comparison in operand of ‘^’ [-Wparentheses] if(a[i] ^ a[j] == 0b1111) ^ user.cpp:46:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("aiacubiti.out","w",stdout); ^ user.cpp: In member function ‘char InParsare::next_char()’: user.cpp:18:39: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer,1,SIZE,stdin); ^ user.cpp: In constructor ‘InParsare::InParsare()’: user.cpp:26:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("aiacubiti.in","r",stdin); ^ user.cpp:28:35: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer,1,SIZE,stdin); ^