CS 1713 Introduction to Computer Science, Spring 2008 String Problems

Write a method that takes a String as a parameter and returns true if and only if:

1. the string has a equal number of upper and lower case letters.
2. the string contains at least two copies of "abc".
3. the string contains exactly two copies of "abc".
4. the string contains two consecuive upper case letters in a row.
5. the string is a valid integer (contains only digits with a possible leading plus or minus sign).