Alexander is learning how to convert numbers from the decimal system to any other, however, he doesn't know English letters, so he writes any number only as a decimal number, it means that instead of the letter A he will write the number 10. Thus, by converting the number 475 from decimal to hexadecimal system, he gets 11311 (475 = 1·162 + 13·161 + 11·160). Alexander lived calmly until he tried to convert the number back to the decimal number system.

Alexander remembers that he worked with little numbers so he asks to find the minimum decimal number so that by converting it to the system with the base n he will get the number k.

Input

The first line contains the integer n (2 ≤ n ≤ 109). The second line contains the integer k (0 ≤ k < 1060), it is guaranteed that the number k contains no more than 60 symbols. All digits in the second line are strictly less than n.

Alexander guarantees that the answer exists and does not exceed 1018.

The number k doesn't contain leading zeros.

Output

Print the number x (0 ≤ x ≤ 1018) — the answer to the problem.

Examples

Input

13
12


Output

12

Input

16
11311


Output

475

Input

20
999


Output

3789

Input

17
2016


Output

594

Note

In the first example 12 could be obtained by converting two numbers to the system with base 13: 12 = 12·130 or 15 = 1·131 + 2·130.
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.*;
import java.util.Map.Entry;

public class TestClass {
	private static InputStream stream;
	private static byte[] buf = new byte[1024];
	private static int curChar;
	private static int numChars;
	private static SpaceCharFilter filter;
	private static PrintWriter pw;
	
	public static class Queue{
		private class node{
			int val;
			node next;
			node(int a){
				val = a;
				next = null;
			}
		}
		node head,tail;
		Queue(){
			head = null;
			tail = null;
		}
		public void EnQueue(int a){
			if(head==null){
				node p = new node(a);
				head = p;
				tail = p;
			}
			else{
				node p = new node(a);
				tail.next = p;
				tail = p;
			}
		}
		public int DeQueue(){
			int a = head.val;
			head = head.next;
			return a;
		}
		public boolean isEmpty(){
			return head==null;
		}
	}
	public static long pow(long x,long y,long m){
		if(y==0)
    		return 1;
    	long k = pow(x,y/2,m);
    	if(y%2==0)
    		return (k*k)%m;
    	else
    		return (((k*k)%m)*x)%m;
    }
	static long Inversex = 0,Inversey = 0;
	public static void InverseModulo(long a,long m){
		if(m==0){
			Inversex = 1;
			Inversey = 0;
		}
		else{
    		InverseModulo(m,a%m);
    		long temp = Inversex;
    		Inversex = Inversey;
    		Inversey = temp+ - (a/m)*Inversey;
    	}
    }
    static long mod1 = 1000000007;
    static long mod2 = 1000000009;
	public static long gcd(long a,long b){
		if(a%b==0)
			return b;
		return gcd(b,a%b);
	}
	public static boolean isPrime(long a){
		if(a==1)
			return false;
		else if(a==2||a==3)
			return true;
		for(long i=2;i<=Math.sqrt(a);i++)
			if(a%i==0)
				return false;
		return true;
	}
	public static double distance(int a,int b,int x,int y){
		return Math.sqrt(((long)(a-x)*(long)(a-x))+((long)(b-y)*(long)(b-y)));
	}
	public static class Pair implements Comparable<Pair> {
		long u;
		long v;
		BigInteger bi;
		public Pair(long u, long v) {
			this.u = u;
			this.v = v;
		}
		public int hashCode() {
			int hu = (int) (u ^ (u >>> 32));
			int hv = (int) (v ^ (v >>> 32));
			return 31 * hu + hv;
		}
		public boolean equals(Object o) {
			Pair other = (Pair) o;
			return u == other.u && v == other.v;
		}
		public int compareTo(Pair other) {
			return Long.compare(u, other.u) != 0 ? Long.compare(u, other.u) : Long.compare(v, other.v);
		}
		public String toString() {
			return u+" "+v;
		}
	}
	public static int sieve(int a[],boolean b[]){
		int count = 0;
		b[0] = true;
		b[1] = true;
		for(int i=2;i<a.length;i++){
			if(!b[i]){
				for(int j=2*i;j<a.length;j=j+i){
					b[j] = true;	
				}
				a[count++] = i;
			}
		}
		return count;
	}
	public static void MatrixMultiplication(int a[][],int b[][],int c[][]){
		for(int i=0;i<a.length;i++){
			for(int j=0;j<b[0].length;j++){
				c[i][j] = 0;
				for(int k=0;k<b.length;k++)
					c[i][j]=(int)((c[i][j]+((a[i][k]*(long)b[k][j])%mod1))%mod1);
			}
		}
	}
	public static void Equal(int arr[][],int temp[][]){
		for(int i=0;i<arr.length;i++){
			for(int j=0;j<arr.length;j++)
				temp[i][j] = arr[i][j];
		}
	}
	public static class Trie {
		Node head;
		private class Node{
			Node a[] = new Node[2];
			boolean val;
			Node(){
				a[0] = null;
				a[1] = null;
				val = false;
			}
		}
		Trie(){
			head = new Node();
		}
		public void insert(Stack<Integer> s){
			Node temp = head;
			while(!s.isEmpty()){
				int q = s.pop();
				if(temp.a[q]==null)
					temp.a[q] = new Node();
				temp = temp.a[q];
			}
			temp.val = true;
		}
		public Node delete(Stack<Integer> s,Node temp){
			if(s.isEmpty())
				return null;
			int q = s.pop();
			temp.a[q] = delete(s,temp.a[q]);
			if(temp.a[q]==null&&temp.a[q^1]==null)
				return null;
			else
				return temp;
		}
		public void get(Stack<Integer> s,Stack<Integer> p){
			Node temp = head;
			while(!p.isEmpty()){
				int q = p.pop();
				if(temp.a[q]!=null){
					s.push(q);
					temp = temp.a[q];
				}
				else{
					s.push(q^1);
					temp = temp.a[q^1];
				}
			}
		}
	}
	/*public static void Merge(long a[][],int p,int r){
        if(p<r){
            int q = (p+r)/2;
            Merge(a,p,q);
            Merge(a,q+1,r);
            Merge_Array(a,p,q,r);
        }
    }
	public static void get(long a[][],long b[][],int i,int j){
		for(int k=0;k<a[i].length;k++)
			a[i][k] = b[j][k];
	}
    public static void Merge_Array(long a[][],int p,int q,int r){
        long b[][] = new long[q-p+1][a[0].length];
        long c[][] = new long[r-q][a[0].length];
        for(int i=0;i<b.length;i++){
            get(b,a,i,p+i);
        }
        for(int i=0;i<c.length;i++){
            get(c,a,i,q+i+1);
        }
        int i = 0,j = 0;
        for(int k=p;k<=r;k++){
            if(i==b.length){
                get(a,c,k,j);
                j++;
            }
            else if(j==c.length){
                get(a,b,k,i);
                i++;
            }
            else if(b[i][0]<c[j][0]){
                get(a,b,k,i);
                i++;
            }
            else{
                get(a,c,k,j);
                j++;
            }
        }
    }
    public static void powMatrix(long n){
    	if(n<=1)
    		return ;
    	powMatrix(n/2);
    	MatrixMultiplication(temp2,temp2,result);
		Equal(result,temp2);
    	if(n%2==1){
    		MatrixMultiplication(temp2,a,result);
    		Equal(result,temp2);
    	}
    }
    static int result[][] = new int[4][4];
	static int temp[][] = new int[4][4];
	static int temp2[][] = new int[4][4];
	static int a[][] = new int[4][4];
	static int[][] b = new int[4][1];
	static int [][] c = new int[4][1];
    public static int count(long n){
		a[0][0] = 1 ;
		a[0][1] = 1;
		a[1][0] = 1;
		a[2][1] = 1;
		a[3][0] = 1;
		a[3][1] = 1;
		a[3][3] = 1;
		b[0][0] = 1;
		b[1][0] = 1;
		b[2][0] = 0;
		b[3][0] = 2;
		Equal(a,temp2);
		result[0][0] = 1;
		result[1][1] = 1;
		result[2][2] = 1;
		result[3][3] = 1;
		Equal(result,temp);
		if(n<=0)
			return 0;
		else if(n==1)
			return 1;
		else if(n==2)
			return 2;
		n = n-2;
		powMatrix(n);
		MatrixMultiplication(temp2,b,c);
		return c[3][0];
	}*/
	public static class SegmentTree{
		long[] arr = new long[5000000];
		long[] lazy = new long[5000000];
		SegmentTree(long a[]){
			Build(a,0,a.length-1,0);
		}
		public void Build(long a[],int p,int q,int r){
			if(p==q){
				arr[r] = a[p];
				return ;
			}
			int mid = (p+q)/2;
			Build(a,p,mid,2*r+1);
			Build(a,mid+1,q,2*r+2);
			arr[r] = Math.min(arr[2*r+1],arr[2*r+2]);
		}
		public long getSum(int p,int q,int x,int y,int z){
			if(lazy[z]!=0){
				arr[z]+=lazy[z];
				lazy[2*z+1]+=lazy[z];
				lazy[2*z+2]+=lazy[z];
				lazy[z] = 0;
			}
			if(y<p||x>q)
				return Long.MAX_VALUE;
			if(p<=x&&q>=y)
				return arr[z];
			int mid = (x+y)/2;
			return Math.min(getSum(p,q,x,mid,2*z+1),getSum(p,q,mid+1,y,2*z+2));
		}
		public void Update(int p,int q,int x,int y,int z,int dif){
			if(lazy[z]!=0){
				arr[z]+=lazy[z];
				lazy[2*z+1] += lazy[z];
				lazy[2*z+2] += lazy[z];
				lazy[z] = 0;
			}
			if(p>y||q<x||p>q)
				return ;
			if(x<=p&&q<=y){
				arr[z]+=dif;
				lazy[2*z+1]+=dif;
				lazy[2*z+2]+=dif;
				return ;
			}
			int mid = (p+q)/2;
			Update(p,mid,x,y,2*z+1,dif);
			Update(mid+1,q,x,y,2*z+2,dif);
			arr[z] = Math.min(arr[2*z+1],arr[2*z+2]);
		}
	}
	private static void soln(){
		Scanner input = new Scanner(System.in);
		long n = input.nextLong();
		long count = 0,k = n;
		long ans = 0;
		while(k!=0){
			count++;
			k/=10;
		}
		long arr[] = new long[(int)count+1];
		arr[0] = 1;
		for(int i=1;i<=count;i++)
			arr[i]=arr[i-1]*10;
		BigInteger nm = BigInteger.valueOf(n);
		BigInteger hlm[] = new BigInteger[(int)count+1];
		for(int i=0;i<=count;i++)
			hlm[i] = BigInteger.valueOf(arr[i]);
		BigInteger p = input.nextBigInteger();
		long temp = 1;
		while(!p.equals(new BigInteger("0"))){
			int j = (int)count;
			for(;j>0;j--){
				if(p.mod(hlm[j]).compareTo(nm)<0&&!p.mod(hlm[j]).equals(p.mod(hlm[j-1]))){
					ans+=p.mod(hlm[j]).longValue()*temp;
					p = p.divide(hlm[j]);
					break;
				}
				//pw.println(ans);
			}
			if(j==0)
				p = p.divide(BigInteger.valueOf(10));
			temp*=n;
		}
		pw.println(ans);
	}
	public static void main(String[] args) {
		InputReader(System.in);
		pw = new PrintWriter(System.out);
		soln();
		pw.close();
	}
	// To Get Input
	// Some Buffer Methods
	public static void InputReader(InputStream stream1) {
		stream = stream1;
	}
	private static boolean isWhitespace(int c) {
		return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
	}
	private static boolean isEndOfLine(int c) {
		return c == '\n' || c == '\r' || c == -1;
	}
	private static int read() {
		if (numChars == -1)
			throw new InputMismatchException();
		if (curChar >= numChars) {
			curChar = 0;
			try {
				numChars = stream.read(buf);
			} catch (IOException e) {
				throw new InputMismatchException();
			}
			if (numChars <= 0)
				return -1;
		}
		return buf[curChar++];
	}
	private static int nI() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		int sgn = 1;
		if (c == '-') {
			sgn = -1;
			c = read();
		}
		int res = 0;
		do {
			if (c < '0' || c > '9')
				throw new InputMismatchException();
			res *= 10;
			res += c - '0';
			c = read();
		} while (!isSpaceChar(c));
		return res * sgn;
	}
	private static long nL() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		int sgn = 1;
		if (c == '-') {
			sgn = -1;
			c = read();
		}
		long res = 0;
		do {
			if (c < '0' || c > '9')
				throw new InputMismatchException();
			res *= 10;
			res += c - '0';
			c = read();
		} while (!isSpaceChar(c));
		return res * sgn;
	}
	private static String nextToken() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		StringBuilder res = new StringBuilder();
		do {
			res.appendCodePoint(c);
			c = read();
		} while (!isSpaceChar(c));
		return res.toString();
	}
	private static String nLi() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		StringBuilder res = new StringBuilder();
		do {
			res.appendCodePoint(c);
			c = read();
		} while (!isEndOfLine(c));
		return res.toString();
	}
	private static int[] nIA(int n) {
		int[] arr = new int[n];
		for (int i = 0; i < n; i++)
			arr[i] = nI();
		return arr;
	}
	private static long[] nLA(int n) {
		long[] arr = new long[n];
		for (int i = 0; i < n; i++)
			arr[i] = nL();
		return arr;
	}
	private static void pArray(int[] arr) {
		for (int i = 0; i < arr.length; i++)
			pw.print(arr[i] + " ");
		pw.println();
		return;
	}
	private static void pArray(long[] arr) {
		for (int i = 0; i < arr.length; i++)
			pw.print(arr[i] + " ");
		pw.println();
		return;
	}
	private static boolean isSpaceChar(int c) {
		if (filter != null)
			return filter.isSpaceChar(c);
		return isWhitespace(c);
	}
	private interface SpaceCharFilter {
		public boolean isSpaceChar(int ch);
	}
}