Compilare: user.cpp: In function 'int cmp(const void*, const void*)': user.cpp:22: warning: unused variable 'd1' user.cpp:22: warning: unused variable 'd2' user.cpp: In function 'int main()': user.cpp:88: warning: use of 'll' length modifier with 'f' type character user.cpp: In function 'int cmp(const void*, const void*)': user.cpp:31: warning: control reaches end of non-void function