@@ -0,0 +1,536 @@
+// http://codingbat.com/prob/p150113%0A%0Apublic String%5B%5D firstSwap(String%5B%5D strings) %7B%0A  Map%3CCharacter, Integer%3E map = new HashMap%3CCharacter, Integer%3E();%0A  for (int i = 0; i %3C strings.length; ++i) %7B%0A    char firstChar = strings%5Bi%5D.charAt(0);%0A    if (!map.containsKey(firstChar)) %7B%0A      map.put(firstChar, i);%0A    %7D%0A    else if (map.get(firstChar) != -1) %7B%0A      String temp = strings%5Bi%5D;%0A      strings%5Bi%5D = strings%5Bmap.get(firstChar)%5D;%0A      strings%5Bmap.get(firstChar)%5D = temp;%0A      map.put(firstChar, -1);%0A    %7D%0A  %7D%0A  return strings;%0A%7D%0A

Create firstSwap.java