diff --git a/day3.ijs b/day3.ijs
new file mode 100644
index 0000000..d9ee4bb
--- /dev/null
+++ b/day3.ijs
@@ -0,0 +1,5 @@
+r =: > cutopen 1!:1 < jpath '~/projects/AoC/2020/year2020day3.txt.cache'
+rn =: 4 : '+/''#''=((#|:y)|x*i.#y){"0 1 y'
+rnx =: 3 : '(1{y) rn 0{"2((0{-y)]\r)'
+rnx 1 3
+*/ rnx"1 (_2 [\ 1 1 1 3 1 5 1 7 2 1)