Compilare: main.cpp: In function 'long long int has(std::string)': main.cpp:19:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 19 | for(int i=0; i<s.length(); i++){ | ~^~~~~~~~~~~ main.cpp: In function 'void solve()': main.cpp:28:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 28 | for(int i=1; i<a.length(); i++){ | ~^~~~~~~~~~~ main.cpp:34:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 34 | for(int i=0; i<a.length(); i++){ | ~^~~~~~~~~~~ main.cpp:42:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 42 | for(int i=a.length(); i<b.length(); i++){ | ~^~~~~~~~~~~ main.cpp:50:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 50 | for(int i=0; i<v.size(); i++){ | ~^~~~~~~~~