#include <iostream> #include <string> bool isSubstring(const std::string& s1, const std::string& s2) { return s1.find(s2) != std::string::npos; } int main() { std::string s1, s2; std::cin >> s1 >> s2; if (isSubstring(s1, s2)) { std::cout << s1 << " is substring of " << s2 << std::endl; } else if (isSubstring(s2, s1)) { std::cout << s2 << " is substring of " << s1 << std::endl; } else { std::cout << "No substring" << std::endl; } return 0; }