Utility to concatenate an array of single digits ([1,2,3]) into an int (123)

gistfile1.java

public class ArrayToIntUtil {

  public static int a2i(int... a) {
    int result = 0;
    int f = (int) Math.pow(10, a.length);
    for (int i : a) result += i * (f /= 10);
    return result;
  }
  
  public static void main(String... args) {
    System.out.println(a2i()); // prints 0
    System.out.println(a2i(6)); // prints 6
    System.out.println(a2i(6, 1, 3, 5, 5, 1)); // prints 613551
  }
  
}