Compilare: main.cpp: In function 'int eval()': main.cpp:47:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 47 | for(int i=0;i<s.size();i++) { | ~^~~~~~~~~ main.cpp:78:17: warning: unused variable 'curr' [-Wunused-variable] 78 | int curr=0; | ^~~~ main.cpp:108:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 108 | while(i<s.size() && s[i]>='0' && s[i]<='9') { | ~^~~~~~~~~