Compilare: user.cpp: In function ‘bool evaluare(std::string)’: user.cpp:28:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<x.size();i++){ ^ user.cpp:32:15: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if(!st.empty()) ^ user.cpp: In function ‘void dehidrogenare(std::string&, std::string&)’: user.cpp:45:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i_i=1;i_i<=i.size();i_i++){ ^ user.cpp: In function ‘bool evaluare(std::string)’: user.cpp:41:1: warning: control reaches end of non-void function [-Wreturn-type] } ^