Compilare: user.cpp: In function ‘int valid(int, int)’: user.cpp:26:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] return HT[pos] && HT[pos] != value; ^ user.cpp: In function ‘bool find(int)’: user.cpp:45:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] return HT[ position( value ) ] == value; ^ user.cpp: In function ‘void erase(int)’: user.cpp:52:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( HT[pos] == value ) HT[pos] = -1; ^ user.cpp: In function ‘unsigned int rd()’: user.cpp:77:10: warning: unused variable ‘c’ [-Wunused-variable] char c; ^