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 {
	
	static InputReader in = new InputReader(System.in);
	static PrintWriter out = new PrintWriter(System.out);
	
	static int oo = (int)1e9;
//	static long oo = (long)1e15;
	static int mod = 1_000_000_007;
//	static int mod = 998244353;
	
	static int[] dx = {0, -1, -1, -1, 0, 1, 1, 1};
	static int[] dy = {-1, -1, 0, 1, 1, 1, 0, -1};
	
	static int M = 1000005;
	static double EPS = 1e-13;
	
	public static void main(String[] args) throws IOException {

		long base = in.nextLong();
		int len = (base+"").length();
		char[] a = in.readString().toCharArray();
		int n = a.length;
		long[] pow = new long[100];
		pow[0] = 1;
		for(int i = 1; i < pow.length; ++i) {
			pow[i] = pow[i-1] * base;
		}
		int x = 0;
		long ans = 0;
		for(int i = n-1; i >= 0; ) {
			long d = 1;
			long num = 0;
			long cur = 0;
			int jj = i;
			for(int j = i, k = Math.max(0, j - len + 1); j >= k; --j) {
				cur += d * (a[j] - '0');
				d *= 10;
				if(j == i || a[j] != '0' && cur < base) {
					num = cur;
					jj = j;
				}
			}
			ans += pow[x++] * num;
			i = jj - 1;
		}
		System.out.println(ans);
		
		
		out.close();
	}
	
	
	static void update(int[] f, int i) {
		while(i < f.length) {
			f[i]++;
			i += (i & -i);
		}
	}
	
	static int query(int[] f, int i) {
		int ret = 0;
		while(i > 0) {
			ret += f[i];
			i -= (i & -i);
		}
		return ret;
	}
	
	static long invmod(long a, long mod) {
		BigInteger b = BigInteger.valueOf(a);
		BigInteger m = BigInteger.valueOf(mod);
		return b.modInverse(m).longValue();
	}
	
	
	static int find(int[] g, int x) {
		return g[x] = g[x] == x ? x : find(g, g[x]);
	}
	
	static void union(int[] g, int[] size, int x, int y) {
		x = find(g, x); y = find(g, y);
		if(x == y)
			return;
		if(size[x] < size[y]) {
			g[x] = y;
			size[y] += size[x];
		}
		else {
			g[y] = x;
			size[x] += size[y];
		}
	}
	
	static class Segment {
		Segment left, right;
		int size;
//		int time, lazy;
		
		public Segment(long[] a, int l, int r) {
			super();
			if(l == r) {
				return;
			}
			int mid = (l + r) / 2;
			left = new Segment(a, l, mid);
			right = new Segment(a, mid+1, r);
		}
		
		boolean covered(int ll, int rr, int l, int r) {
			return ll <= l && rr >= r;
		}
		
		boolean noIntersection(int ll, int rr, int l, int r) {
			return ll > r || rr < l;
		}
		
//		void lazyPropagation() {
//			if(lazy != 0) {
//				if(left != null) {
//					left.setLazy(this.time, this.lazy);
//					right.setLazy(this.time, this.lazy);
//				}
//				else {
//					val = lazy;
//				}
//			}
//		}
		
//		void setLazy(int time, int lazy) {
//			if(this.time != 0 && this.time <= time)
//				return;
//			this.time = time;
//			this.lazy = lazy;
//		}
		
		
		int querySize(int ll, int rr, int l, int r) {
//			lazyPropagation();
			if(noIntersection(ll, rr, l, r))
				return 0;
			if(covered(ll, rr, l, r))
				return size;
			int mid = (l + r) / 2;
			int leftSize = left.querySize(ll, rr, l, mid);
			int rightSize = right.querySize(ll, rr, mid+1, r);
			return leftSize + rightSize;
		}
		
		int query(int k, int l, int r) {
			Segment trace = this;
			while(l < r) {
				int mid = (l + r) / 2;
				if(trace.left.size > k) {
					trace = trace.left;
					r = mid;
				}
				else {
					k -= trace.left.size;
					trace = trace.right;
					l = mid + 1;
				}
			}
			return l;
		}
		
		void update(int ll, int rr, int l, int r) {
//			lazyPropagation();
			if(noIntersection(ll, rr, l, r))
				return;
			if(covered(ll, rr, l, r)) {
//				setLazy(time, knight);
				this.size = 1;
				return;
			}
			int mid = (l + r) / 2;
			left.update(ll, rr, l, mid);
			right.update(ll, rr, mid+1, r);
			this.size = left.size + right.size;
		}
	}
	
	static long pow(long a, long n, long mod) {
		if(n == 0)
			return 1;
		if(n % 2 == 1)
			return a * pow(a, n-1, mod) % mod;
		long x = pow(a, n / 2, mod);
		return x * x % mod;
	}
	
	
	static int[] getPi(char[] a) {
		int m = a.length;
		int j = 0;
		int[] pi = new int[m];
		for(int i = 1; i < m; ++i) {
			while(j > 0 && a[i] != a[j])
				j = pi[j-1];
			if(a[i] == a[j]) {
				pi[i] = j + 1;
				j++;
			}
		}
		return pi;
	}
	
	static long lcm(long a, long b) {
		return a * b / gcd(a, b);
	}
	
	static BigInteger lcm2(long a, long b) {
		long g = gcd(a, b);
		BigInteger gg = BigInteger.valueOf(g);
		BigInteger aa = BigInteger.valueOf(a);
		BigInteger bb = BigInteger.valueOf(b);
		return aa.multiply(bb).divide(gg);
	}
	
	static boolean nextPermutation(int[] a) {
		for(int i = a.length - 2; i >= 0; --i) {
			if(a[i] < a[i+1]) {
				for(int j = a.length - 1; ; --j) {
					if(a[i] < a[j]) {
						int t = a[i];
						a[i] = a[j];
						a[j] = t;
						for(i++, j = a.length - 1; i < j; ++i, --j) {
							t = a[i];
							a[i] = a[j];
							a[j] = t;
						}
						return true;
					}
				}
			}
		}
		return false;
	}
	
	static void shuffle(Object[] a) {
		Random r = new Random();
		for(int i = a.length - 1; i > 0; --i) {
			int si = r.nextInt(i);
			Object t = a[si];
			a[si] = a[i];
			a[i] = t;
		}
	}
	
	static void shuffle(int[] a) {
		Random r = new Random();
		for(int i = a.length - 1; i > 0; --i) {
			int si = r.nextInt(i);
			int t = a[si];
			a[si] = a[i];
			a[i] = t;
		}
	}
	
	static void shuffle(long[] a) {
		Random r = new Random();
		for(int i = a.length - 1; i > 0; --i) {
			int si = r.nextInt(i);
			long t = a[si];
			a[si] = a[i];
			a[i] = t;
		}
	}
	
	static int lower_bound(int[] a, int n, int k) {
		int s = 0;
		int e = n;
		int m;
		while (e - s > 0) {
			m = (s + e) / 2;
			if (a[m] < k)
				s = m + 1;
			else
				e = m;
		}
		return e;
	}
	static int lower_bound(long[] a, int n, long k) {
		int s = 0;
		int e = n;
		int m;
		while (e - s > 0) {
			m = (s + e) / 2;
			if (a[m] < k)
				s = m + 1;
			else
				e = m;
		}
		return e;
	}
	
	static int gcd(int a, int b) {
		return b == 0 ? a : gcd(b, a % b);
	}
	static long gcd(long a, long b) {
		return b == 0 ? a : gcd(b, a % b);
	}
	static BigInteger gcd(BigInteger a, BigInteger b) {
		return b.compareTo(BigInteger.ZERO) == 0 ? a : gcd(b, a.mod(b));
	}
	
	static class Pair implements Comparable<Pair> {
		int first, second;
 
		public Pair(int first, int second) {
			super();
			this.first = first;
			this.second = second;
		}
 
		@Override
		public int compareTo(Pair o) {
			return this.first != o.first ? this.first - o.first : this.second - o.second;
		}
		
//		@Override
//		public int compareTo(Pair o) {
//			return this.first != o.first ? o.first - this.first : o.second - this.second;
//		}
 
		@Override
		public int hashCode() {
			final int prime = 31;
			int result = 1;
			result = prime * result + first;
			result = prime * result + second;
			return result;
		}
 
		@Override
		public boolean equals(Object obj) {
			if (this == obj)
				return true;
			if (obj == null)
				return false;
			if (getClass() != obj.getClass())
				return false;
			Pair other = (Pair) obj;
			if (first != other.first)
				return false;
			if (second != other.second)
				return false;
			return true;
		}
	}
}
 
 
 
class InputReader {
 
	private final InputStream stream;
	private final byte[] buf = new byte[8192];
	private int curChar, snumChars;
 
	public InputReader(InputStream st) {
		this.stream = st;
	}
 
	public int read() {
		if (snumChars == -1)
			throw new InputMismatchException();
		if (curChar >= snumChars) {
			curChar = 0;
			try {
				snumChars = stream.read(buf);
			} catch (IOException e) {
				throw new InputMismatchException();
			}
			if (snumChars <= 0)
				return -1;
		}
		return buf[curChar++];
	}
 
	public int nextInt() {
		int c = read();
		while (isSpaceChar(c)) {
			c = read();
		}
		int sgn = 1;
		if (c == '-') {
			sgn = -1;
			c = read();
		}
		int res = 0;
		do {
			res *= 10;
			res += c - '0';
			c = read();
		} while (!isSpaceChar(c));
		return res * sgn;
	}
 
	public long nextLong() {
		int c = read();
		while (isSpaceChar(c)) {
			c = read();
		}
		int sgn = 1;
		if (c == '-') {
			sgn = -1;
			c = read();
		}
		long res = 0;
		do {
			res *= 10;
			res += c - '0';
			c = read();
		} while (!isSpaceChar(c));
		return res * sgn;
	}
 
	public int[] nextIntArray(int n) {
		int a[] = new int[n];
		for (int i = 0; i < n; i++) {
			a[i] = nextInt();
		}
		return a;
	}
 
	public String readString() {
		int c = read();
		while (isSpaceChar(c)) {
			c = read();
		}
		StringBuilder res = new StringBuilder();
		do {
			res.appendCodePoint(c);
			c = read();
		} while (!isSpaceChar(c));
		return res.toString();
	}
 
	public String nextLine() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		StringBuilder res = new StringBuilder();
		do {
			res.appendCodePoint(c);
			c = read();
		} while (!isEndOfLine(c));
		return res.toString();
	}
 
	public boolean isSpaceChar(int c) {
		return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
	}
 
	private boolean isEndOfLine(int c) {
		return c == '\n' || c == '\r' || c == -1;
	}
 
}