package pr01;

public class VeryBigInteger {

   private static String digits = "0123456789";
   private static int base = 10;

   private int[] vals;

   public VeryBigInteger(String numString) {
      vals = new int[numString.length()];
      for (int i = 0; i < vals.length; i++)
         vals[i] = digits.indexOf(numString.charAt(numString.length() - i - 1));
   }

   private VeryBigInteger(int[] vals) {
      this.vals = vals;
   }
 
   private VeryBigInteger add(VeryBigInteger op2) {
      int[] newVals;
      int len;
      int carry = 0;
      len = Math.max(vals.length, op2.vals.length) + 1;
      newVals = new int[len];
      for (int i = 0; i < len; i++) {
         newVals[i] = carry;
         carry = 0;
         if (i < vals.length)
            newVals[i] = newVals[i] + vals[i];
         if (i < op2.vals.length)
            newVals[i] = newVals[i] + op2.vals[i];
         if (newVals[i] >= base) {
            newVals[i] = newVals[i] - base;
            carry = 1;
         }
      }
      return new VeryBigInteger(newVals);
   }

   public String toString() {
      String s = "";
      for (int i = 0; i < vals.length; i++)
         s = digits.charAt(vals[i]) + s;
      return s;
   }

}