diff --git a/Day 4/code.py b/Day 4/code.py
new file mode 100644
index 0000000..af3919f
--- /dev/null
+++ b/Day 4/code.py	
@@ -0,0 +1,37 @@
+start = 272091
+end = 815432
+
+index = start
+
+count = 0
+
+
+def ascending(index):
+    for i in range(len(str(index)) - 1):
+
+        a, b = str(index)[i], str(index)[i + 1]
+
+        if a > b:
+            index += 10 ** (len(str(index)) - i - 2) * abs(int(b) - int(a))
+            return ascending(index)
+            break
+    return index
+
+
+while True:
+    index = ascending(index)
+
+    if index > end:
+        break
+
+    for i in range(len(str(index)) - 1):
+        a, b = str(index)[i], str(index)[i + 1]
+
+        if a == b:
+            count += 1
+            print(index)
+            break
+
+    index += 1
+
+print(count)