Compilare: user.cpp: In function ‘int main()’: user.cpp:29:16: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (ch==')') ^ user.cpp:33:16: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (ch==']') ^ user.cpp:37:16: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (ch=='*') ^