diff --git a/2015/04/4.md b/2015/04/4.md
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+## \-\-- Day 4: The Ideal Stocking Stuffer \-\--
+
+Santa needs help [mining](https://en.wikipedia.org/wiki/Bitcoin#Mining)
+some AdventCoins (very similar
+to [bitcoins](https://en.wikipedia.org/wiki/Bitcoin)) to use as gifts
+for all the economically forward-thinking little girls and boys.
+
+To do this, he needs to find [MD5](https://en.wikipedia.org/wiki/MD5)
+hashes which, in
+[hexadecimal](https://en.wikipedia.org/wiki/Hexadecimal), start with at
+least *five zeroes*. The input to the MD5 hash is some secret key (your
+puzzle input, given below) followed by a number in decimal. To mine
+AdventCoins, you must find Santa the lowest positive number (no leading
+zeroes: `1`, `2`, `3`, \...) that produces such a hash.
+
+For example:
+
+-   If your secret key is `abcdef`, the answer is `609043`, because the
+    MD5 hash of `abcdef609043` starts with five zeroes
+    (`000001dbbfa...`), and it is the lowest such number to do so.
+-   If your secret key is `pqrstuv`, the lowest number it combines with
+    to make an MD5 hash starting with five zeroes is `1048970`; that is,
+    the MD5 hash of `pqrstuv1048970` looks like `000006136ef...`.
+
+Your puzzle answer was `254575`.
+
+## \-\-- Part Two \-\-- {#part2}
+
+Now find one that starts with *six zeroes*.
+
+Your puzzle answer was `1038736`.
+
+Both parts of this puzzle are complete! They provide two gold stars:
+\*\*
+
+At this point, you should [return to your Advent calendar](/2015) and
+try another puzzle.
+
+Your puzzle input was `bgvyzdsv`{.puzzle-input}.
+
diff --git a/2015/04/solution.py b/2015/04/solution.py
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+++ b/2015/04/solution.py
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+#!/bin/python3
+import sys,re,hashlib
+from pprint import pprint
+sys.path.insert(0, '../../')
+from fred import list2int
+
+input_f = 'input'
+
+part = 2
+#########################################
+#                                       #
+#              Part 1                   #
+#                                       #
+#########################################
+
+if part == 1:
+    result = 0
+    count = 0
+    found = False
+    with open(input_f) as file:
+        for line in file:
+            tmp = line.rstrip()
+            while found == False:
+                m = hashlib.md5()
+                text = tmp + str(count)
+                #print(text)
+                m.update(text.encode('UTF-8'))
+                nr = m.hexdigest()
+                #print(nr)
+
+                if nr[0:5] == '00000':
+                    print(count)
+                    #print(text)
+                    #print(nr)
+                    found = True
+                else:
+                    count += 1
+                #print(nr[ 0 : 5 ])
+            found = False
+
+
+
+
+#########################################
+#                                       #
+#              Part 2                   #
+#                                       #
+#########################################
+if part == 2:
+    result = 0
+    count = 0
+    found = False
+    with open(input_f) as file:
+        for line in file:
+            tmp = line.rstrip()
+            while found == False:
+                m = hashlib.md5()
+                text = tmp + str(count)
+                #print(text)
+                m.update(text.encode('UTF-8'))
+                nr = m.hexdigest()
+                #print(nr)
+
+                if nr[0:6] == '000000':
+                    print(count)
+                    #print(text)
+                    #print(nr)
+                    found = True
+                else:
+                    count += 1
+                #print(nr[ 0 : 5 ])
+            found = False
+