Compilare: main.cpp: In function 'int main()': main.cpp:10:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 10 | for(int i=0;i<s.size();i++){ | ~^~~~~~~~~ main.cpp:13:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 13 | while(i<s.size()&&((s[i]>='A'&&s[i]<='Z')||(s[i]>='0'&&s[i]<='9'))){ | ~^~~~~~~~~ main.cpp:20:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 20 | while(i<s.size()&&((s[i]>='a'&&s[i]<='z')||(s[i]>='0'&&s[i]<='9'))){ | ~^~~~~~~~~ main.cpp:35:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 35 | for(int j=0;j<s.size();j++){ | ~^~~~~~~~~