#include<stdio.h>
#include<string.h>

int main()
{
    int i=0,j=0;
    char s1[20],s2[20];
	char ch;

	while((ch=getchar())!='\n')
	{
		s1[i++]=ch;
	}
	s1[i]='\0'; 
	while((ch=getchar())!='\n')
	{
		s2[j++]=ch;
	}
	s2[j]='\0';
	
		if(	strstr(s1,s2)!=NULL)
		{
			printf("%s is substring of %s",s2,s1);
			return 0;
		}
    printf("No substring");
	return 0;
	}