Question

For example, if I call exchangePairs(“abcdefg”), I should receive “badcfeg” in return.

This is for a homework assignment, any kind of pseudocode would be very helpful. I am just beginning to learn recursion and up until this problem I haven’t had too much of an issue.

Answer 1

public String swapPairs(String s) {
     if (s.length() < 2)
          return s;
     else
          return swap(s.charAt(0), s.charAt(1)) + swapPairs(s.substring(2));
}