Compilare: main.cpp: In function 'int mult()': main.cpp:33:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 33 | while(pos<s.size()&&(s[pos]=='*' || s[pos]=='/')) | ~~~^~~~~~~~~ main.cpp: In function 'int add()': main.cpp:52:14: 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(pos<s.size()&&(s[pos]=='+' || s[pos]=='-')) | ~~~^~~~~~~~~ main.cpp:66:1: warning: control reaches end of non-void function [-Wreturn-type] 66 | } | ^