Compilare: main.cpp: In function 'int main()': main.cpp:22:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 22 | while(j<s[i-1].size() && j<s[i].size() && s[i-1][j]==s[i][j]) | ~^~~~~~~~~~~~~~ main.cpp:22:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 22 | while(j<s[i-1].size() && j<s[i].size() && s[i-1][j]==s[i][j]) | ~^~~~~~~~~~~~