Question

This is a simple array declaration and initialization.

  int arr[] = new int[10];

    for(int i = 0; i<arr.length; i++){

    arr[i] = i;
    }

This

System.out.println(arr[000001]); 

to

System.out.println(arr[000007]);

prints out the correct values but anything above 8

System.out.println(arr[000008]);

produces a java.lang.RuntimeException: Uncompilable source code

Why does this happen?

Answer 1

This has nothing to do with arrays; integers starting with the digit 0 are octal (base 8). The legal octal digits are 0-7, so that 08 (or 00000008) are invalid octal integer literals. The correct octal for 8 is 010.