diff --git a/day15.py b/day15.py
new file mode 100644
index 0000000..e4e51dd
--- /dev/null
+++ b/day15.py
@@ -0,0 +1,29 @@
+import aoclib
+
+DAY = 15
+TEST_SOLUTION_PART1 = 436
+TEST_SOLUTION_PART2 = 175594
+
+
+def part1(test_mode=False, count=2020):
+    my_input = aoclib.getInputAsArraySplit(day=DAY, return_type=int, split_char=",", test=test_mode)
+
+    memory_last = {v: i for i, v in enumerate(my_input)}
+    memory_prev = {}
+    last_spoken = my_input[-1]
+
+    for i in range(len(my_input), count):
+        if last_spoken not in memory_prev:
+            last_spoken = 0
+        else:
+            last_spoken = i - 1 - memory_prev[last_spoken]
+
+        if last_spoken in memory_last:
+            memory_prev[last_spoken] = memory_last[last_spoken]
+        memory_last[last_spoken] = i
+
+    return last_spoken
+
+
+def part2(test_mode=False):
+    return part1(test_mode, count=30000000)
diff --git a/inputs/15 b/inputs/15
new file mode 100644
index 0000000..08ea36b
--- /dev/null
+++ b/inputs/15
@@ -0,0 +1 @@
+16,12,1,0,15,7,11
diff --git a/inputs/15_test b/inputs/15_test
new file mode 100644
index 0000000..c84ffe7
--- /dev/null
+++ b/inputs/15_test
@@ -0,0 +1 @@
+0,3,6