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.*;
import java.math.BigInteger;
import java.util.*;

public class Main {
    public static void main(String[] args) throws FileNotFoundException {
        ConsoleIO io = new ConsoleIO(new InputStreamReader(System.in), new PrintWriter(System.out));
        //ConsoleIO io = new ConsoleIO(new FileReader("D:\\fbhc\\beach_umbrellas.txt"), new PrintWriter(new File("D:\\fbhc\\out.txt")));
        new Main(io).solve();
        io.close();
    }
    ConsoleIO io;
    Main(ConsoleIO io) {
        this.io = io;
    }

    long MOD = 1_000_000_007;
    int N, M, W, K, Q;

    class Edge{
        public Edge(int _w, int _s, int _u, int _v){
            we = _w;
            st = _s;
            u = _u;
            v = _v;
        }
        public int we;
        public int st;
        public int u;
        public int v;

        public int getOther(int cur){
            return cur==u?v:u;
        }
    }

    Edge[] all;
    long[] minRem;
    long[] maxRem;
    long[] tot;
    ArrayList<ArrayList<Edge>> gr;

    public void solve() {
//        int n = io.ri();
//        gr = new ArrayList<>();
//        all = new Edge[n-1];
//        minRem = new long[n];
//        maxRem = new long[n];
//        tot = new long[n];
//        for(int i = 0;i<n;i++)gr.add(new ArrayList<>());
//        for(int i = 0;i<n-1;i++){
//            int u= io.ri(),v = io.ri(), w = io.ri(), s = io.ri();
//            Edge edge = new Edge(w,s,u,v);
//            gr.get(u).add(edge);
//            gr.get(v).add(edge);
//            all[i] = edge;
//        }

        String n = io.readLine();
        String k = io.readLine();

        long base = Long.parseLong(n);

        long[] min = new long[k.length()+1];
        long lim = ((long)10e18)/base;
        for(int i = 1;i<=k.length();i++){
            long mul = 1;
            long val = 0;
            long ans = Long.MAX_VALUE;
            for(int j = i-1;j>=0;j--){
                if(mul>base)break;
                val+=mul*(k.charAt(j)-'0');
                mul*=10;
                if(val>=base)break;
                long prev= min[j];
                if(prev>lim)continue;
                if(k.charAt(j)=='0' && mul>10)continue;
                long next = prev*base+val;
                ans = Math.min(next, ans);
            }
            min[i] = ans;
        }

        io.writeLine(min[k.length()] + "");

    }

    int have(int cur, int from){
        ArrayList<Edge> ch = gr.get(cur);
        int min=0;
        int max=0;
        for(int i = 0;i<ch.size();i++){
            Edge e = ch.get(i);

            int u = e.getOther(cur);
            int t = have(u,cur);
           // if()
        }

        minRem[cur] = min;
        maxRem[cur] = max;
        return 0;
    }

}

class ConsoleIO {
    BufferedReader br;
    PrintWriter out;
    public ConsoleIO(Reader reader, PrintWriter writer){br = new BufferedReader(reader);out = writer;}
    public void flush(){this.out.flush();}
    public void close(){this.out.close();}
    public void writeLine(String s) {this.out.println(s);}
    public void writeInt(int a) {this.out.print(a);this.out.print(' ');}
    public void writeWord(String s){
        this.out.print(s);
    }
    public void writeIntArray(int[] a, int k, String separator) {
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < k; i++) {
            if (i > 0) sb.append(separator);
            sb.append(a[i]);
        }
        this.writeLine(sb.toString());
    }
    public int read(char[] buf, int len){try {return br.read(buf,0,len);}catch (Exception ex){ return -1; }}
    public String readLine() {try {return br.readLine();}catch (Exception ex){ return "";}}
    public long[] readLongArray() {
        String[]n=this.readLine().trim().split("\\s+");long[]r=new long[n.length];
        for(int i=0;i<n.length;i++)r[i]=Long.parseLong(n[i]);
        return r;
    }
    public int[] readIntArray() {
        String[]n=this.readLine().trim().split("\\s+");int[]r=new int[n.length];
        for(int i=0;i<n.length;i++)r[i]=Integer.parseInt(n[i]);
        return r;
    }
    public int[] readIntArray(int n) {
        int[] res = new int[n];
        char[] all = this.readLine().toCharArray();
        int cur = 0;boolean have = false;
        int k = 0;
        boolean neg = false;
        for(int i = 0;i<all.length;i++){
            if(all[i]>='0' && all[i]<='9'){
                cur = cur*10+all[i]-'0';
                have = true;
            }else if(all[i]=='-') {
                neg = true;
            }
            else if(have){
                res[k++] = neg?-cur:cur;
                cur = 0;
                have = false;
                neg = false;
            }
        }
        if(have)res[k++] = neg?-cur:cur;
        return res;
    }
    public int ri() {
        try {
            int r = 0;
            boolean start = false;
            boolean neg = false;
            while (true) {
                int c = br.read();
                if (c >= '0' && c <= '9') {
                    r = r * 10 + c - '0';
                    start = true;
                } else if (!start && c == '-') {
                    start = true;
                    neg = true;
                } else if (start || c == -1) return neg ? -r : r;
            }
        } catch (Exception ex) {
            return -1;
        }
    }
    public long readLong() {
        try {
            long r = 0;
            boolean start = false;
            boolean neg = false;
            while (true) {
                int c = br.read();
                if (c >= '0' && c <= '9') {
                    r = r * 10 + c - '0';
                    start = true;
                } else if (!start && c == '-') {
                    start = true;
                    neg = true;
                } else if (start || c == -1) return neg ? -r : r;
            }
        } catch (Exception ex) {
            return -1;
        }
    }
    public String readWord() {
        try {
            boolean start = false;
            StringBuilder sb = new StringBuilder();
            while (true) {
                int c = br.read();
                if (c!= ' ' && c!= '\r' && c!='\n' && c!='\t') {
                    sb.append((char)c);
                    start = true;
                } else if (start || c == -1) return sb.toString();
            }
        } catch (Exception ex) {
            return "";
        }
    }
    public char readSymbol() {
        try {
            while (true) {
                int c = br.read();
                if (c != ' ' && c != '\r' && c != '\n' && c != '\t') {
                    return (char) c;
                }
            }
        } catch (Exception ex) {
            return 0;
        }
    }
    public char readChar(){try {return (char)br.read();}catch (Exception ex){ return 0; }}
}