> 原文:[https://www . geesforgeks . org/number format-setminimumentegerdigits-method-in-Java-with-examples/](https://www.geeksforgeeks.org/numberformat ...

WRITE A FUNCTION THAT ACCEPTS A USER INPUT PHONE NUMBER AS A STRING AND RETURNS A NORMALIZED UNITED STATES PHONE NUMBER IN E.164 FORMAT. RETURN NULL (OR AN EQUIVALENT VALUE) IF THE USER INPUT IS ...