Compilare: main.cpp: In function 'int main()': main.cpp:22:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 22 | for (int i=0; i<s.size(); i++){ | ~^~~~~~~~~ main.cpp:31:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 31 | while (i<s.size() && s[i]>='a' && s[i]<='z'){ | ~^~~~~~~~~ main.cpp:43:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 43 | while(i < s.size() && s[i] >= '0' && s[i] <= '9'){ | ~~^~~~~~~~~~ main.cpp:55:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 55 | while(i < s.size() && s[i] >= '0' && s[i] <= '9'){ | ~~^~~~~~~~~~