Answers for "calculate leading zeros in a string"

python convert number to string with leading zeros

str(1).zfill(2)
# 1 will be '01'

str(23).zfill(4)
# 23 will be '0023'

replace 2 leading zeros from string

String str = "00051700";
String strPattern = "^0+";        
System.out.println( "String: " + str.replaceAll(strPattern, "") );