Compilare: user.cpp:56:2: warning: no newline at end of file user.cpp: In function 'void back(int, int)': user.cpp:18: warning: name lookup of 'i' changed user.cpp:2: warning: matches this 'i' under ISO standard rules user.cpp:8: warning: matches this 'i' under old rules user.cpp:19: warning: name lookup of 'j' changed user.cpp:2: warning: matches this 'j' under ISO standard rules user.cpp:11: warning: matches this 'j' under old rules