Added a solution

varunu28 · varunu28 · commit 93943bb108d2 · 2018-07-18T21:32:28.000-07:00
diff --git a/Easy/Buddy Strings.java b/Easy/Buddy Strings.java
@@ -0,0 +1,25 @@
+class Solution {
+	public static boolean buddyStrings(String A, String B) {
+	    if (A.length() != B.length() || A.length() <= 1 || B.length() <= 1) {
+	        return false;
+	    }
+        
+        if (A.equals(B)) {
+            Set<Character> s = new HashSet<Character>();
+            for (char c : A.toCharArray()) {
+                s.add(c);
+            }
+            
+            return s.size() < A.length();
+        }
+        
+        List<Integer> dif = new ArrayList<>();
+        for (int i = 0; i < A.length(); ++i) {
+            if (A.charAt(i) != B.charAt(i)) {
+                dif.add(i);
+            }
+        }
+        
+        return dif.size() == 2 && A.charAt(dif.get(0)) == B.charAt(dif.get(1)) && A.charAt(dif.get(1)) == B.charAt(dif.get(0)); 
+	}
+}
