#include <iostream>
#include <fstream>
#include <unordered_map>

using namespace std;

ifstream input_stream;
ofstream output_stream;


int findAnagramPos(string content, string title) {
	const uint32_t CONTENT_LEN = content.length();
	const uint32_t TITLE_LEN = title.length();

	unordered_map<char, uint32_t> target, anagram;
	for (uint32_t i = 0; i < TITLE_LEN; i++) {
		target[title[i]]++;
		anagram[content[i]]++;
	}

	if (target == anagram) {
		return 0;
	}

	for (uint32_t i = TITLE_LEN; i < CONTENT_LEN; i++) {
		/**
		Old first character pos = i - TITLE_LEN
		New first character pos = i - TITLE_LEN + 1
		Old last character pos = i - 1
		New last character pos = i
		*/
		char firstChar = content[i - TITLE_LEN];
		anagram[firstChar]--;

		if (anagram[firstChar] == 0) {
			anagram.erase(firstChar);
		}

		anagram[content[i]]++;

		if (target == anagram) {
			return i - TITLE_LEN;
		}
	}

	return -1;
}


int main() {
	input_stream.open("input.txt");

	string content, title;
	input_stream >> content;
	input_stream >> title;

	cout << findAnagramPos(content, title) << endl;	

	input_stream.close();
	return 0;
}