import std.conv, std.functional, std.range, std.stdio, std.string;
import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, 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)); }


long rev(long a) {
  char[] s = a.to!string.dup;
  s.reverse;
  return s.to!long;
}

void main() {
  try {
    for (; ; ) {
      const P = readLong;
      const Q = readLong;
      const X = readLong;
      const Y = readLong;
      
      // rev: q 0...0 y
      long q = Q;
      for (; q % 10 == 0 || rev(q) % P == X; q += Q) {}
      long y = Y;
      for (; y % 10 == 0 || rev(y) % P == 0; y += Q) {}
      debug {
        writeln("q = ", q, ", y = ", y);
      }
      
      const a = rev(y) % P;
      long r = rev(q) % P;
      int cnt;
      long ten = (10L^^(q.to!string.length)) % P;
      for (; (ten * a + r) % P != X; ) {
        ++cnt;
        ten = (ten * 10) % P;
      }
      
      char[] ans;
      ans ~= q.to!string;
      ans ~= '0'.repeat(cnt).array;
      ans ~= y.to!string;
      debug {
        assert(BigInt(ans) % Q == Y);
      }
      ans.reverse;
      debug {
        assert(BigInt(ans) % P == X);
      }
      writeln(ans);
    }
  } catch (EOFException e) {
  }
}