// Factorial function
fact(n) {
  if (n == 0) { return 1; }
  else { return n*fact(n-1); }
}

// String length function
strlen (s) {
  var i; i = 0;
  while (s[i] != 0) i = i + 1;
  return i;
}

// String concatenation function (s must have enough length)
strcat(s, t) {
  var i,j;
  i = strlen(s); j = 0;
  while (t[j] != 0) {
    s[i] = t[j];
    i = i + 1;
    j = j + 1;
  }
  s[i] = 0;
  return s;
}

// Main routine
main() {
  var ln[80], n;
  writeln('N?');
  n = str2int(readln(ln));

  var buf[80];
  buf[0]=0;
  strcat(buf,int2str(ln, n));
  strcat(buf,'! =');
  strcat(buf,int2str(ln, fact(n)));
  writeln(buf);
}