diff --git a/2021/nim/day25.nim b/2021/nim/day25.nim
index eeaa766..0556c12 100644
--- a/2021/nim/day25.nim
+++ b/2021/nim/day25.nim
@@ -1,7 +1,18 @@
-import ./common, std/[strutils, sequtils, tables, strformat, algorithm]
+import ./common, std/[strutils, sequtils, tables, strformat, algorithm, hashes]
 
 proc p1(input: Lines): uint64 =
-  0
+  var cukes = input
+  while cukes.hash != nextCukes.hash
+    var nextCukes = cukes
+    for y,line in cukes:
+      for x,c in cukes:
+        case c:
+          # don't forget to wrap
+          of '>': # TODO: check next x
+          of 'v': # TODO: check next y
+          else: continue
+    cukes = nextCukes
+    inc result
 
 proc p2(input: Lines): uint64 =
   0