Compilare: main.cpp: In function 'int expression()': main.cpp:16:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 16 | while (p < s.length() && (s[p] == '+' || s[p] == '-')) { | ~~^~~~~~~~~~~~ main.cpp: In function 'int term()': main.cpp:30:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 30 | while (p < s.length() && (s[p] == '*' || s[p] == '/')) { | ~~^~~~~~~~~~~~ main.cpp: In function 'int factor()': main.cpp:56:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 56 | while (p < s.length() && isdigit(s[p])) { | ~~^~~~~~~~~~~~