Compilare: main.cpp: In function 'int expresie()': main.cpp:27:50: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 27 | while ((str[i] == 'M' || str[i] == 'm') && i < str.size()) { | ~~^~~~~~~~~~~~ main.cpp: In function 'int termen()': main.cpp:47:52: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 47 | while (str[i] >= '0' && str[i] <= '9' && i < str.size()) { | ~~^~~~~~~~~~~~