Converting an int into an array without converting it to a String [duplicate]

问题

I am programming in Java and want to convert an int into an array. For example I want to convert 122 into {1, 2, 2}. Do you have an idea how this works? Thanks in advance. I am not allowed to convert it into a string.

回答1:

Here is the answer without using Math class

import java.util.Arrays;
class int_to_array
{
    public static void main(String arg[])
    {
        int number = 122;
        int length=0;
        int org=number;
        while(org!=0)
        {
            org=org/10;
            length++;
        }
        int[] array = new int[length];

        for(int i = 0; i < length; i++) {
          int rem = number % 10; 
          array[length - i - 1] = rem;
          number = number / 10; 
        }

        System.out.println(Arrays.toString(array));
    }
}

回答2:

The following example uses pure arithmetical approach (without converting the number to string):

int number = 122;
List<Integer> digitList = new LinkedList<>();

while(number > 0) {
  int d = number % 10; //get last digit
  digitList.add(0, d);
  number = number / 10; //omit last digit
}

Integer[] digits = digitList.toArray(new Integer[0]);
System.out.println(Arrays.toString(digits));

回答3:

This ends up in an endless loop - why that?

    int input = readInt("Bitte geben Sie eine positive Zahl ein:");
    while(input < 0) {
        input = readInt("Bitte geben Sie eine positive Zahl ein:");
    }
    int number = input;
    int length = 0;
    int org = number;
    while(org != 0) {
        org = org / 10;
        length++;
    }
    int[] inputArray = new int[length];
    int i = 0;
    while(i < inputArray.length) {
        int rem = number % 10;
        inputArray[length - i - 1] = rem;
        number = number / 10;
 i++;
    }
    String output = "{";
    i = 0;
    while(i < inputArray.length) {
        output += inputArray[i];
        if(i < inputArray.length-1) {
            output += ", ";
        }
        i++;
    }
    output += "}";
    System.out.print(output);

来源：https://stackoverflow.com/questions/47254379/converting-an-int-into-an-array-without-converting-it-to-a-string

标签

java

arrays

int