Update readme and lib and start 2015.

2015/d4.py

@@ -0,0 +1,22 @@
+from lib import *
+import hashlib
+
+part_1 = True
+
+if part_1:
+    digits = 5
+else:
+    digits = 6
+
+data = open(0).read().strip()
+
+for i in range(10**9):
+    text = data + str(i)
+    md5_hash = hashlib.md5(text.encode()).hexdigest()
+    for c in md5_hash[:digits]:
+        if c != "0":
+            break
+    else:
+        print(i)
+        break
+