public class Bigfact {

  public static void main (String args[]) {

    int i, j, n, N;
    int carry, mmax, mmax_s, mmul;
    int mufactor, zeros;

    int MUNITNUM = 65535;
    int LIMIT_N = 15000;
    int DIGIT_UNIT = 4;

    carry = mmax = mmax_s = mmul = 0;
    mufactor = 10000;

    String[] z = new String[DIGIT_UNIT];
    String zero = "";
    for (int k = 0; k < DIGIT_UNIT; k++) {
      z[k] = zero;
      zero = zero + "0";
    }

    int[] s = new int[MUNITNUM];
    s[0] = 1;

    Integer NI = new Integer(args[0]);
    N = NI.intValue();

    for (i = 2; i <= N; i++) {
      mmax_s = mmax;
      for (j = 0; j <= mmax_s; j++) {
        n = s[j];
        mmul = n * i + carry;
        carry = mmul / mufactor;
        mmul %= mufactor;
        s[j] = mmul;
        if ((carry != 0) && (j == mmax)) {
          mmax++;
          s[mmax] = carry;
          carry = 0;
        }
      }
    }

  for (i = mmax; i >= 0; i--) {

    zeros = 0;

    if (i != mmax) {
      if (s[i] < 10)
        zeros = 3;
      if (s[i] < 100)
        zeros = 2;
      if (s[i] < 1000)
        zeros = 1;

      System.out.print(z[zeros]);
    }
    System.out.print(s[i]);
  }

  System.out.println("");
  System.exit (0);
  }
}