Compilare: main.cpp: In function 'int main()': main.cpp:24:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 24 | for (int i = 0; i < s1. size() - 1; i++) | ~~^~~~~~~~~~~~~~~~ main.cpp:31:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 31 | for (int i = 0; i < s1.size(); i++) | ~~^~~~~~~~~~~ main.cpp:43:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 43 | for (int i = s1.size(); i < s2.size(); i++) | ~~^~~~~~~~~~~