Compilare: main.cpp: In function 'int main()': main.cpp:30:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 30 | for ( int st = 1; st < s[0].size() - len + 1; st++ ) { | ~~~^~~~~~~~~~~~~~~~~~~~~~~ main.cpp:48:30: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 48 | for ( int st = 1; st < s[i].size() - len + 1; st++ ) { | ~~~^~~~~~~~~~~~~~~~~~~~~~~