Note on comparisons: lexicographic comparison between strings

A string s precedes a string t in lexicographic order if

• s is a prefix of t, or
• if c and d are respectively the first character of s and t in which s and t differ, then c precedes d in character order.

Note: For the characters that are alphabetical letters, the character order coincides with the alphabetical order. Digits precede letters, and uppercase letters precede lowercase ones.

Example:

• house precedes household
• Household precedes house
• composer precedes computer
• H2O precedes HOTEL

To verify whether a string precedes another one in lexicographic order, we use the compareTo() method. Given two strings s and t, s.compareTo(t) returns

• a negative integer, if s precedes t;
• 0, if s is equal to t, i.e., if s.equals(t) returns true;
• a positive integer, if s follows t.