Compilare: user.cpp: In function ‘void polishform()’: user.cpp:44:6: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if (strchr("+-*/",s[i])) if (st.empty()) st.push(s[i]); ^ user.cpp: In function ‘int prior(char)’: user.cpp:18:1: warning: control reaches end of non-void function [-Wreturn-type] } ^