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javaarrayssortingnumbersdigits

Dividing large number into separate digits and store them

So if I for example have a large number, say 18750409. I would like to divide this number into separate digits to 1,8,7,5,0,4,0,9. But I don't want to print them out right away, I would like to store them somewhere, like a number A for 1, number B for 8. (In an array possibly?) So I can do more things with these numbers later in the program before printing out results.

Any help is appreciated!

Solution

  • 1) Get the length (# of digits) of your number (can be done by converting the number to a string and getting the length by calling .length();

    int number = ...;
String my_string = "" + number;
int numberLength = my_string.length();

    2) Use a for loop to cycle through your string, and make a separate array of characters and as you go through each char of your string using charAt(), store them in that array:

    char[] charArray;
charArray = new char[numberLength];

for(int i = 0; i < (numberLength - 1); i++) // -> Remember, -1 because arrays start at 0!
{
  charArray[i] = my_string.charAt(i);
}

    Now you have an array of the digits in char form. To convert them back into ints, just cycle through that array and convert the char back to a number. Note: you can also store the digits as strings.

    If you are using chars, to convert to int: use getNumericValue() -> this technically returns unicode numerical value, but unicode of a digit is that digit.

    int[] digitArray;
digitArray = new int[numberLength];

for (int i =0; i< numberLength; i++)
{
 digitArray[i] = charArray[i].getNumericValue();
}

    And thats it. :) (Sorry if some of the java syntax is off; I have not done java in quite some time.