Compilare: main.cpp: In function 'int main()': main.cpp:13:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 13 | for(int i = 0;i < s.size();i++) | ~~^~~~~~~~~~ main.cpp:14:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 14 | for(int j = i + 1;j < s.size();j++) | ~~^~~~~~~~~~ main.cpp:15:29: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 15 | for(int k = 0;k < s.size() - j;k++) | ~~^~~~~~~~~~~~~~