Compilare: user.cpp: In function ‘int main()’: user.cpp:9:12: warning: variable ‘a’ set but not used [-Wunused-but-set-variable] int i, x, a, b, c, d; ^ user.cpp:9:15: warning: variable ‘b’ set but not used [-Wunused-but-set-variable] int i, x, a, b, c, d; ^ user.cpp:9:18: warning: variable ‘c’ set but not used [-Wunused-but-set-variable] int i, x, a, b, c, d; ^