import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.complex, std.container, std.math, std.numeric, std.regex, std.typecons;
import core.bitop;

class EOFException : Throwable { this() { super("EOF"); } }
string[] tokens;
string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; }
int readInt() { return readToken.to!int; }
long readLong() { return readToken.to!long; }
real readReal() { return readToken.to!real; }

bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } }
bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } }

int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; }
int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); }
int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); }


int B;
string D;

int L;

void normalize(int[] a) {
  foreach (i; 0 .. L + 10) {
    int q = a[i] / B, r = a[i] % B;
    if (r < 0) {
      --q;
      r += B;
    }
    a[i + 1] += q;
    a[i] = r;
  }
}

void main() {
  try {
    for (; ; ) {
      B = readInt();
      D = readToken();
      
      L = cast(int)(D.length);
      auto d = new int[L + 20];
      foreach (i; 0 .. L) {
        d[i] = D[L - 1 - i] - '0';
      }
      debug {
        writeln("d = ", d);
      }
      
      /*
        min n s.t. d <= Sum[1 <= k <= n] k (B - 1) B^(k-1)
          <=> (B - 1) d <= n B^(n+1) - (n + 1) B^n + 1
      */
      
      // d *= (B - 1)
      foreach_reverse (i; 0 .. L) {
        d[i + 1] += d[i];
        d[i] *= -1;
      }
      d.normalize;
      debug {
        writeln("d = ", d);
      }
      
      int lo = 0, hi = L + 1;
      for (; lo + 1 < hi; ) {
        const mid = (lo + hi) / 2;
        auto e = new int[L + 20];
        e[0] += 1;
        e[mid] -= (mid + 1);
        e[mid + 1] += mid;
        e.normalize;
        int s;
        foreach_reverse (i; 0 .. L + 10) {
          if (d[i] != e[i]) {
            s = sgn(d[i] - e[i]);
            break;
          }
        }
        ((s <= 0) ? hi : lo) = mid;
      }
      const n = hi;
      debug {
        writeln("n = ", n);
      }
      
      foreach (k; 1 .. n) {
        // d -= (B - 1) . k (B - 1) B^(k-1)
        d[k - 1] -= (B - 1) * k * (B - 1);
      }
      d.normalize;
      debug {
        writeln("d = ", d);
      }
      
      int rem;
      
      // f = d / (B - 1)
      auto f = new int[L + 20];
      rem = 0;
      foreach_reverse (i; 0 .. L + 10) {
        rem = rem * B + d[i];
        f[i] = rem / (B - 1);
        rem %= (B - 1);
      }
      assert(rem == 0);
      debug {
        writeln("f = ", f);
      }
      
      // f -= 1, g = d / n
      --f[0];
      f.normalize;
      auto g = new int[L + 20];
      rem = 0;
      foreach_reverse (i; 0 .. L + 10) {
        rem = rem * B + f[i];
        g[i] = rem / n;
        rem %= n;
      }
      debug {
        writeln("g = ", g);
        writeln("rem = ", rem);
      }
      
      // rem-th (0-based) significant digit of B^(n-1) + g
      g[n - 1] += 1;
      const ans = g[n - 1 - rem];
      writeln(ans);
    }
  } catch (EOFException e) {
  }
}