#include #include

using namespace std;

string s,t;

bool check(string s,string t){ //判定t是否是s的子串 for (int i=0;i<s.length();i++){ bool flag = true; for (int j=0;j<t.length();j++) if (s[i+j] != t[j]) flag = false; if (flag) return 1; } return 0; }

int main(){ cin >> s >> t; if (s.length() < t.length()) swap(s,t); //让s一定是较长的串

if (check(s,t))	
	cout << t << " is substring of " << s;
else
	cout << "No substring";

}