Compilare: user.cpp: In function ‘int bt(int)’: user.cpp:42:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int check(int)’: user.cpp:46:12: warning: unused variable ‘s’ [-Wunused-variable] int j, s; ^ user.cpp: In function ‘int show(int)’: user.cpp:112:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^