long s = Long.parseLong("49906281183");
long d = 0, a = 0;
int p =1;
Scanner in = new Scanner(
System.in);
System.out.print("Ввод w: ");
long w = in.nextInt();
if (w > 0) {
long ww = 0;
for (int i = 0; i < w; Math.round(w / 10)) {
long c = w % 10;
long k = c + a + d;
s = s + (k % 10) * p;
d = Math.round(k / 10);
a = c;
p = p * 10;
w = Math.round(w / 10);
ww = w;
if (w < 0) s = s + (a + d) * p;
}
System.out.println("w === : " + ww);
}
На java вот такое получилось