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.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Random;

/**
 * @author Ivan Pryvalov (ivan.pryvalov@gmail.com)
 */
public class CF392_Div2_D implements Runnable {

    static EventType eventType = EventType.DEFAULT;
//    static EventType eventType = EventType.GOOGLE_CODE_JAM;

    // Set T=0 if T should be read from input.
    // Set T=1 if there is only one testcase.
    static int T = 1;

    // Set it to `null' when the input is std in.
//    static String inputFilename = null;
//    static String inputFilename = "A-sample.in";
//    static String inputFilename = "A-small-attempt0.in";
    static String inputFilename = null;


    // Set to true if you have prepared a large test with fake data.
    static boolean largeFakeTest = false;
    //Number of tests in the large fake test.
    static int largeFakeTest_T = 1;


    //--------------------------------------------------------------------


    public static class Solver extends  SolverAbstract{
        long N; // 10^9
        char[] K; // 60 chars
        String S;

        @Override
        public void readInput() throws IOException {
            N = scanner.nextInt();
            S = scanner.nextToken();
            K = S.toCharArray();
        }

        @Override
        protected String solve() throws IOException {
            List<Long> digits = new ArrayList<>();

            //try greedy
            int cur_pos = K.length - 1;
            while (cur_pos >= 0){
                for(int delta=9; delta>=0; delta--){
                    if (cur_pos-delta<0)
                        continue;
                    String candidate = S.substring(cur_pos-delta, cur_pos+1);
                    if (candidate.length()>1 && candidate.charAt(0)=='0'){
                        continue;
                    }
                    Long candidateLong = Long.parseLong(candidate);
                    if (candidateLong >= N){
                        continue;
                    }
                    //found!
                    digits.add(candidateLong);
                    //System.out.println("added "+candidateLong);
                    cur_pos = cur_pos - delta - 1;
                    break;
                }
            }
            long res = 0;
            long multiplier = 1;
            for (long digit : digits){
                res += digit * multiplier;
                multiplier *= N;
            }

            return "" + res;
        }
    }

    // ------------- Some stardard tools that are currently not tested.

    static class Graph{
        int[][] G;
        int N;

        int[][] A;
        int[][] F;

        int[] path;
        int pathLen;
        boolean[] visited;
        int target;
        boolean flowFound;

        public Graph(int[][] g) {
            G = g;
            N = G.length;
        }

        public int[][] maxflow(int iSource, int iSink) {
            path = new int[N];
            visited = new boolean[N];

            A = new int[N][];
            for (int i = 0; i < N; i++) {
                A[i] = G[i].clone();
            }
            F = new int[N][N];

            target = iSink;
            //dfs from source to sink
            //increase path
            while(true){
                flowFound = false;
                visited[iSource] = true;
                pathLen = 0;
                path[pathLen++] = iSource;
                dfs(iSource);
                if (!flowFound)
                    break;
            }
            return F;
        }

        private void dfs(int u) {
            if (u==target){
                flowFound = true;
                for (int i = 0; i < pathLen-1; i++) {
                    int from = path[i];
                    int to  = path[i+1];
                    F[from][to]++;
                    F[to][from]--;
                }
            }else {
                for (int i = 0; i < N && !flowFound; i++) {
                    if (!visited[i] && A[u][i] > F[u][i]) {
                        visited[i] = true;
                        path[pathLen] = i;
                        pathLen++;
                        dfs(i);
                        visited[i] = false;
                        pathLen--;
                    }
                }
            }
        }
    }

    //--------------------------------------------------------------------

    private void solveAll() throws IOException, InterruptedException {
        long timeStart = System.currentTimeMillis();

        if (T==0) {
            if (largeFakeTest) {
                T = largeFakeTest_T;
            } else {
                T = scanner.nextInt();
            }
        }
        final String[] results = new String[T+1];
        for (int test = 0; test < T; test++) {
            Solver solver = new Solver(){
                @Override
                public void callback() {
                    results[testNo] = answer;
                }
            };
            solver.testNo = test+1;
            if (largeFakeTest) {
                solver.readFakeInput();
            }else{
                solver.readInput();
            }
            solver.solveWrapped();
        }

        long timeEnd = System.currentTimeMillis();
        if (isInputFromFile())
            System.out.println("All tasks are solved! Elapsed time "+(timeEnd-timeStart)/1000.0+" sec.");

        // write all responses in the proper order
        for (int i = 1; i <= T; i++) {
            if (eventType == EventType.GOOGLE_CODE_JAM){
                out.printf("Case #%d: %s", i, results[i]);
            }else {
                out.println(results[i]);
            }
        }
    }

    enum EventType{
        DEFAULT,
        GOOGLE_CODE_JAM
    }

    static boolean isInputFromFile() {
        return inputFilename != null;
    }

    public static abstract class SolverAbstract {
        int testNo;
        String answer = null;

        public void callback(){};

        public abstract void readInput() throws IOException;

        //generate a randomized test with the maximal input values
        public void readFakeInput() throws  IOException{
            throw new RuntimeException("not implemented");
        }

        protected abstract String solve() throws IOException;

        protected void solveWrapped() throws IOException {

            if (isInputFromFile())
                System.out.println("SOLVER: solving task #"+testNo+" out of "+ T+"...");

            answer = solve();
/*
            StringBuilder sbAnswer = new StringBuilder();
            sbAnswer.append(String.format("Case #%d:\n", testNo));
            good.forEach( (k,v) -> {
                sbAnswer.append(k).append(" ");
                for(int x:v){
                    sbAnswer.append(x).append(" ");
                }
                sbAnswer.append("\n");
            });


            answer = sbAnswer.toString();
*/

            if (isInputFromFile()) {
                System.out.println("\t"+answer);
            }
            callback();
        }

    }

    ////////////////////////////////////////////////////////

    /**
     * Source: http://stackoverflow.com/questions/4521983/java-executorservice-that-blocks-on-submission-after-a-certain-queue-size
     *
     * @param <E>
     */
//    public class LimitedQueue<E> extends LinkedBlockingQueue<E>{
//
//        public LimitedQueue(int maxSize) {
//            super(maxSize);
//        }
//
//        @Override
//        public boolean offer(E e){
//            // turn offer() and add() into a blocking calls (unless interrupted)
//            try {
//                put(e);
//                return true;
//            } catch(InterruptedException ie) {
//                Thread.currentThread().interrupt();
//            }
//            return false;
//        }
//    }

    /**
     * Move to Utilities
     *
     * //List<Integer> primesLimited = getPrimes(1_000_000).subList(0, 100);
     *
     * @param limit
     * @return
     */
    public static List<Integer> getPrimes(int limit) {
        boolean[] primes = new boolean[limit+1];
        Arrays.fill(primes, true);

        primes[1] = false;
        for(int i=2; i<=limit; i++){
            if (primes[i]){
                for(int j=i+i; j<=limit; j+=i){
                    primes[j] = false;
                }
            }
        }
        List<Integer> listPrimes = new ArrayList<>();
        for(int i=2; i<=limit; i++){
            if (primes[i]){
                listPrimes.add(i);
            }
        }
        return listPrimes;
    }


    public static class Modulo{
        long mod = (long)1e9+7;

        public Modulo(long mod) {
            super();
            this.mod = mod;
        }

        public long inv(long a) {
            long res =  pow(a, mod-2);
            return res;
        }

        public long pow(long a, long x) {
            if (x==0)
                return 1;
            long part = 1;
            if ((x&1)!=0)
                part = a;
            return (part * pow((a*a)%mod, x>>1)) % mod;
        }

        public long c(long n, long m){
            long res = 1;
            for(int i=1; i<=m; i++){
                res = (res * (n-m+i)) % mod;
                res = (res * inv(i)) % mod;
            }
            return res;
        }
    }

    /**
     * Added 26.04.2013.
     * See KROK 2013, Round 1, Problem D.
     */
    static class DisjointUnionSet implements Cloneable{
        int[] rank;
        int[] parent;

        protected DisjointUnionSet clone(){
            DisjointUnionSet cloned = new DisjointUnionSet(parent.length);
            for(int i=0; i<parent.length; i++){
                cloned.parent[i] = parent[i];
                cloned.rank[i] = rank[i];
            }
            return cloned;
        }

        public DisjointUnionSet(int n) {
            rank = new int[n];
            parent = new int[n];
            for (int i = 0; i < n; i++) {
                parent[i] = i;
            }
        }

        @Override
        public String toString() {
            return "disj [parents=" + Arrays.toString(parent) + "]";
        }

        /**
         * Problem specific or general?
         * O(N * alpha)
         */
        public void union(DisjointUnionSet set2){
            for(int i=0; i<parent.length; i++){
                parent[find(i)] = parent[find(set2.find(i))];
            }
        }

        /**
         * @param index1 range 0..n-1
         * @param index2
         */
        public void union(int index1, int index2){
            int p1 = find(index1);
            int p2 = find(index2);
            if (rank[p1] > rank[p2]){
                parent[p2] = p1;
            }else if (rank[p2] > rank[p1]){
                parent[p1] = p2;
            }else{
                parent[p2] = p1;
                rank[p1]++;
            }
        }

        // O(alpha(n))
        private int find(int index) {
            if (parent[index] != index)
                parent[index] =  find(parent[index]);
            return parent[index];
        }

        // O(N alpha(N)) ==> see find()
        public int getCountDisjointSets(){
            int[] used = new int[parent.length];
            for(int i=0; i<parent.length; i++){
                used[find(i)] = 1;
            }
            int res = 0;
            for(int i=0; i<parent.length; i++){
                res += used[i];
            }
            return res;
        }
    }

    private static Random rnd = new Random();
    public static class ArrayUtils{
        public static void shuffle(int[] a){
            for(int j=a.length-1; j>=1; j--){
                int i = rnd.nextInt(j+1);
                swap(a, i, j);
            }
        }

        public static void swap(int[] a, int i, int j){
            int tmp = a[i];
            a[i] = a[j];
            a[j] = tmp;
        }
    }

    ////////////////////////////////////////////////////////
    /// Typically, you don't want to edit anything below
    ///////////////////////////////////////////////////////
    final int BUF_SIZE = 1024 * 1024 * 8;//important to read long-string tokens properly
    final int INPUT_BUFFER_SIZE = 1024 * 1024 * 8 ;
    final int BUF_SIZE_INPUT = 1024;

    final int BUF_SIZE_OUT = 1024;

    boolean useClassResourceTopDir = true;
    String outSuffix = ".out";

    //InputStream bis;
    //OutputStream bos;
    static PrintStream out;
    static ByteScanner scanner;
    static ByteWriter writer;

    public void run() {
        try{
            InputStream bis = null;
            OutputStream bos = null;
            if (inputFilename !=null){

                File inputFile = null;
                File outputFile = null;
                if (useClassResourceTopDir) {
                    File baseFile = new File(getClass().getResource("/").getFile());
                    inputFile = new File(baseFile, inputFilename);
                    outputFile = new File(baseFile, inputFilename +outSuffix);
                }else{
                    inputFile = new File(inputFilename);
                    outputFile = new File(inputFilename +outSuffix);
                }
                System.out.println("Input file canonical path: "+inputFile.getCanonicalPath());
                bis = new BufferedInputStream(
                        new FileInputStream(inputFile),
                        INPUT_BUFFER_SIZE);
                bos = new BufferedOutputStream(new FileOutputStream(outputFile));
                out = new PrintStream(bos);
            }else{
                bis = new BufferedInputStream(System.in, INPUT_BUFFER_SIZE);
                bos = new BufferedOutputStream(System.out);
                out = new PrintStream(bos);
            }
            scanner = new ByteScanner(bis, BUF_SIZE_INPUT, BUF_SIZE);
            writer = new ByteWriter(bos, BUF_SIZE_OUT);

            solveAll();
            out.flush();
        }catch (Exception e) {
            e.printStackTrace();
            System.exit(1);
        }
    }

    public interface Constants{
        byte ZERO = '0';//48 or 0x30
        byte NINE = '9';
        byte SPACEBAR = ' '; //32 or 0x20
        byte MINUS = '-'; //45 or 0x2d

        char FLOAT_POINT = '.';
    }

    public static class EofException extends IOException{
    }

    public static class ByteWriter implements Constants {

        int bufSize = 1024;
        byte[] byteBuf = new byte[bufSize];
        OutputStream os;

        public ByteWriter(OutputStream os, int bufSize){
            this.os = os;
            this.bufSize = bufSize;
        }

        public void writeInt(int num) throws IOException{
            int byteWriteOffset = byteBuf.length;
            if (num==0){
                byteBuf[--byteWriteOffset] = ZERO;
            }else{
                int numAbs = Math.abs(num);
                while (numAbs>0){
                    byteBuf[--byteWriteOffset] = (byte)((numAbs % 10) + ZERO);
                    numAbs /= 10;
                }
                if (num<0)
                    byteBuf[--byteWriteOffset] = MINUS;
            }
            os.write(byteBuf, byteWriteOffset, byteBuf.length - byteWriteOffset);
        }

        /**
         * Please ensure ar.length <= byteBuf.length!
         *
         * @param ar
         * @throws IOException
         */
        public void writeByteAr(byte[] ar) throws IOException{
            for (int i = 0; i < ar.length; i++) {
                byteBuf[i] = ar[i];
            }
            os.write(byteBuf,0,ar.length);
        }

        public void writeSpaceBar() throws IOException{
            byteBuf[0] = SPACEBAR;
            os.write(byteBuf,0,1);
        }

    }

    public static class ByteScanner implements Constants{

        InputStream is;

        public ByteScanner(InputStream is, int bufSizeInput, int bufSize){
            this.is = is;
            this.bufSizeInput = bufSizeInput;
            this.bufSize = bufSize;

            byteBufInput = new byte[this.bufSizeInput];
            byteBuf = new byte[this.bufSize];
        }

        public ByteScanner(byte[] data){
            byteBufInput = data;
            bufSizeInput = data.length;
            bufSize = data.length;
            byteBuf = new byte[bufSize];
            byteRead = data.length;
            bytePos = 0;
        }

        private int bufSizeInput;
        private int bufSize;

        byte[] byteBufInput;
        byte by=-1;
        int byteRead=-1;
        int bytePos=-1;

        byte[] byteBuf;
        int totalBytes;

        boolean eofMet = false;

        private byte nextByte() throws IOException{

            if (bytePos<0 || bytePos>=byteRead){
                byteRead = is==null? -1: is.read(byteBufInput);
                bytePos=0;
                if (byteRead<0){
                    byteBufInput[bytePos]=-1;//!!!
                    if (eofMet)
                        throw new EofException();
                    eofMet = true;
                }
            }
            return byteBufInput[bytePos++];
        }

        /**
         * Returns the next meaningful character as byte.<br>
         *
         * @return
         * @throws IOException
         */
        public byte nextChar() throws IOException{
            while ((by=nextByte())<=0x20);
            return by;
        }

        /**
         * Returns the next meaningful character OR space as byte.<br>
         *
         * @return
         * @throws IOException
         */
        public byte nextCharOrSpacebar() throws IOException{
            while ((by=nextByte())<0x20);
            return by;
        }

        /**
         * Reads line.
         *
         * @return
         * @throws IOException
         */
        public String nextLine() throws IOException {
            readToken((byte)0x20);
            return new String(byteBuf,0,totalBytes);
        }

        public byte[] nextLineAsArray() throws IOException {
            readToken((byte)0x20);
            byte[] out = new byte[totalBytes];
            System.arraycopy(byteBuf, 0, out, 0, totalBytes);
            return out;
        }

        /**
         * Reads token. Spacebar is separator char.
         *
         * @return
         * @throws IOException
         */
        public String nextToken() throws IOException {
            readToken((byte)0x21);
            return new String(byteBuf,0,totalBytes);
        }

        /**
         * Spacebar is included as separator char
         *
         * @throws IOException
         */
        private void readToken() throws IOException {
            readToken((byte)0x21);
        }

        private void readToken(byte acceptFrom) throws IOException {
            totalBytes = 0;
            while ((by=nextByte())<acceptFrom);
            byteBuf[totalBytes++] = by;
            while ((by=nextByte())>=acceptFrom){
                byteBuf[totalBytes++] = by;
            }
        }

        public int nextInt() throws IOException{
            readToken();
            int num=0, i=0;
            boolean sign=false;
            if (byteBuf[i]==MINUS){
                sign = true;
                i++;
            }
            for (; i<totalBytes; i++){
                num*=10;
                num+=byteBuf[i]-ZERO;
            }
            return sign?-num:num;
        }

        public long nextLong() throws IOException{
            readToken();
            long num=0;
            int i=0;
            boolean sign=false;
            if (byteBuf[i]==MINUS){
                sign = true;
                i++;
            }
            for (; i<totalBytes; i++){
                num*=10;
                num+=byteBuf[i]-ZERO;
            }
            return sign?-num:num;
        }

		/*
		//TODO test Unix/Windows formats
		public void toNextLine() throws IOException{
			while ((ch=nextChar())!='\n');
		}
		*/

        public double nextDouble() throws IOException{
            readToken();
            char[] token = new char[totalBytes];
            for (int i = 0; i < totalBytes; i++) {
                token[i] = (char)byteBuf[i];
            }
            return Double.parseDouble(new String(token));
        }

        public int[] loadIntArray(int size) throws IOException{
            int[] a = new int[size];
            for (int i = 0; i < a.length; i++) {
                a[i] = nextInt();
            }
            return a;
        }

        public long[] loadLongArray(int size) throws IOException{
            long[] a = new long[size];
            for (int i = 0; i < a.length; i++) {
                a[i] = nextLong();
            }
            return a;
        }
    }

    public static void main(String[] args) {
        new CF392_Div2_D().run();
    }
}