Compilare: main.cpp: In function 'int Termen()': main.cpp:23:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 23 | while(idx < s.size() && (s[idx] <= '9' && s[idx] >= '0')) | ~~~~^~~~~~~~~~ main.cpp: In function 'int Eval_Inm_Imp()': main.cpp:34:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 34 | while(idx < s.size() && (s[idx] == '*' || s[idx] == '/')) | ~~~~^~~~~~~~~~ main.cpp: In function 'int Eval_Plus_Minus()': main.cpp:52:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 52 | while(idx < s.size() && (s[idx] == '+' || s[idx] == '-')) | ~~~~^~~~~~~~~~