Compilare: user.cpp: In function ‘int main()’: user.cpp:19:15: warning: suggest parentheses around assignment used as truth value [-Wparentheses] if (a=1990) ^ user.cpp:31:15: warning: suggest parentheses around assignment used as truth value [-Wparentheses] if (a=2002) ^ user.cpp:43:15: warning: suggest parentheses around assignment used as truth value [-Wparentheses] if (a=2014) ^