diff --git a/ayb.py b/ayb.py
new file mode 100755
index 0000000..abdbb94
--- /dev/null
+++ b/ayb.py
@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+
+def ayb(s):
+    A = [None] * 128
+    Q = []
+    c = 1
+    for i in range(len(s)):
+        code = ord(s[i])
+        if A[code] is None:
+            A[code] = c
+            if c == 1:
+                c = 0
+            elif c == 0:
+                c = 2
+            else:
+                c += 1
+        Q.append((A[code],i))
+
+    if c == 1:
+        c = 0
+    if c == 0:
+        c = 2
+
+    num = 0
+    for tup in Q:
+        value, position = tup
+        num += value * (c ** (len(s) - position - 1))
+
+    return str(num)
+
+
+def main():
+    t = int(input())
+    for i in range(1, t + 1):
+        print("Case #" + str(i) + ": " + ayb(input()))
+
+if __name__ == "__main__":
+    main()
diff --git a/ayb.txt b/ayb.txt
new file mode 100644
index 0000000..ea49633
--- /dev/null
+++ b/ayb.txt
@@ -0,0 +1,4 @@
+3
+11001001
+cats
+zig
diff --git a/tree.c b/tree.c
new file mode 100644
index 0000000..2ed96c5
--- /dev/null
+++ b/tree.c
@@ -0,0 +1,5 @@
+// vim: set ts=4 sw=4 et tw=80 :
+#include <stdio.h>
+
+int main() {
+
diff --git a/tree.py b/tree.py
new file mode 100755
index 0000000..24e8259
--- /dev/null
+++ b/tree.py
@@ -0,0 +1,60 @@
+#!/usr/bin/env python3
+
+def min_remove(D):
+    m = len(D)
+    for k in range(1, len(D)):
+        BT = []
+        V = [None] * len(D)
+        r = len(D) - 1 - max_edges(D, BT, V, k)
+        if m is None or r < m:
+            m = r
+    return m
+
+
+def max_edges(D, BT, V, k):
+    if V[k] is None:
+        BT.append(k)
+        if len(D[k]) <= 1: # Either one edge (parent) or two (parent and one child)
+            BT.remove(k)
+            V[k] = 1
+        else:
+            m1 = None
+            m2 = None
+            for e in D[k]:
+                if e in BT:
+                    continue
+                d = max_edges(D, BT, V, e)
+                if m1 is None or d > m1:
+                    m2 = m1
+                    m1 = d
+                elif m2 is None or d > m2:
+                    m2 = d
+            BT.remove(k)
+            if m2 is None:
+                V[k] = 1
+            else:
+                V[k] = 1 + m1 + m2
+    return V[k]
+
+
+if __name__ == "__main__":
+    t = int(input())
+    for i in range(1, t+1):
+        n = int(input())
+        D = [None] * (n+1)
+        for j in range(n-1):
+            string = input().split(' ')
+            a, b = int(string[0]), int(string[1])
+
+            if D[a] is None:
+                D[a] = [b]
+            else:
+                D[a].append(b)
+
+            if D[b] is None:
+                D[b] = [a]
+            else:
+                D[b].append(a)
+
+        print("Case #" + str(i) + ": " + str(min_remove(D)))
+
diff --git a/tree.txt b/tree.txt
new file mode 100644
index 0000000..990e806
--- /dev/null
+++ b/tree.txt
@@ -0,0 +1,15 @@
+3
+3
+2 1
+1 3
+7
+4 5
+4 2
+1 2
+3 1
+6 4
+3 7
+4
+1 2
+2 3
+3 4