Given are two strings s and t consisting of lowercase English letters. Determine if there exists an integer i satisfying the following condition, and find the minimum such i if it exists.

* Let s' be the concatenation of 10^{100} copies of s. t is a subsequence of the string {s'}_1{s'}_2\ldots{s'}_i (the first i characters in s').

Constraints

* 1 \leq |s| \leq 10^5
* 1 \leq |t| \leq 10^5
* s and t consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:


s
t


Output

If there exists an integer i satisfying the following condition, print the minimum such i; otherwise, print `-1`.

Examples

Input

contest
son


Output

10


Input

contest
programming


Output

-1


Input

contest
sentence


Output

33
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Random;
import java.util.StringTokenizer;
import java.util.TreeSet;

public class Main {
	
	public static void main(String[] args) {
		FastReader scan = new FastReader();
		PrintWriter out = new PrintWriter(System.out);
		Task solver = new Task();
		solver.solve(1, scan, out);
		out.close();
	}
	
	static class Task {
		public void solve(int testNumber, FastReader scan, PrintWriter out) {
			char[] s = scan.next().toCharArray();
			char[] t = scan.next().toCharArray();
			int[][] after = new int[s.length+1][26];
			long total = 0;
			int at = 0;
			for(int i = 0; i < after.length; i++) Arrays.fill(after[i], -1);
			for(int i = s.length-1; i >= 0; i--) {
				for(int j = 0; j < 26; j++) after[i][j] = after[i+1][j];
				after[i][s[i]-'a'] = i+1;
			}
			for(int i = 0; i < t.length; i++) {
				int next = after[at][t[i]-'a'];
				if(next == -1) {
					total += s.length-at;
					next = after[at=0][t[i]-'a'];
				}
				if(next == -1) {
					out.println(-1);
					return;
				}
				total += next - at;
				at = next;
			}
			out.println(total);
		}
	}
	
	static void shuffle(int[] a) {
		Random get = new Random();
		for(int i = 0; i < a.length; i++) {
			int r = get.nextInt(a.length);
			int temp = a[i];
			a[i] = a[r];
			a[r] = temp;
		}
	}
	
	static void shuffle(long[] a) {
		Random get = new Random();
		for(int i = 0; i < a.length; i++) {
			int r = get.nextInt(a.length);
			long temp = a[i];
			a[i] = a[r];
			a[r] = temp;
		}
	}
	

	static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		public FastReader() {
			br = new BufferedReader(new InputStreamReader(System.in));
		}
		public FastReader(String s) throws FileNotFoundException {
			br = new BufferedReader(new FileReader(new File(s)));
		}

		String next() {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt() {
			return Integer.parseInt(next());
		}

		long nextLong() {
			return Long.parseLong(next());
		}

		double nextDouble() {
			return Double.parseDouble(next());
		}

		String nextLine() {
			String str = "";
			try {
				str = br.readLine();
			} catch (IOException e) {
				e.printStackTrace();
			}
			return str;
		}
	}

}
