Compilare: user.cpp: In function ‘int main()’: user.cpp:58:23: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(s->info=='(') ^ user.cpp:50:19: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(ch==']') ^ user.cpp:71:15: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(ch=='E') ^