Compilare: user.cpp: In function ‘void insert(int)’: user.cpp:12: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘void deelet(int)’: user.cpp:24: warning: comparison between signed and unsigned integer expressions user.cpp:22: warning: unused variable ‘p’ user.cpp:22: warning: unused variable ‘a’ user.cpp:22: warning: unused variable ‘b’ user.cpp:23: warning: unused variable ‘ok’ user.cpp: In function ‘bool find(int)’: user.cpp:34: warning: comparison between signed and unsigned integer expressions