Day 9 JS

R/.Rproj.user/shared/notebooks/paths

@@ -26,6 +26,7 @@
 /Users/hrbrmstr/Development/2020-code-advent/js/03.js="E24752E6"
 /Users/hrbrmstr/Development/2020-code-advent/js/04.js="CB04A9CB"
 /Users/hrbrmstr/Development/2020-code-advent/js/05.js="AFC9E61D"
+/Users/hrbrmstr/Development/2020-code-advent/js/08.js="E730C21E"
 /Users/hrbrmstr/Development/2020-code-advent/scala/01/01/src/main/scala/Main.scala="8F03A1D5"
 /Users/hrbrmstr/Development/2020-code-advent/scala/02/02/src/main/scala/Main.scala="418A1A5F"
 /private/tmp/test.txt="1CB0AD22"

R/09.R

@@ -75,9 +75,9 @@ input <- as.numeric(read_lines("../input/09-01.txt"))
 preamble_length <- 25
 window <- 1:preamble_length
 input_start <- preamble_length + 1
-no_sum_found <- TRUE
+condition <- TRUE
 
-while(no_sum_found && (length(input)>=(preamble_length + 1))) {
+while(condition && (length(input)>=(preamble_length + 1))) {
 
   as.data.frame(t(combn(window, 2))) %>%
     mutate(
@@ -86,9 +86,9 @@ while(no_sum_found && (length(input)>=(preamble_length + 1))) {
       sum = input[V1] + input[V2]
     ) -> pair_sums
 
-  no_sum_found <- any(pair_sums$sum == input[input_start])
+  condition <- any(pair_sums$sum == input[input_start])
 
-  if (no_sum_found) input <- tail(input, -1)
+  if (condition) input <- tail(input, -1)
 
 }
 
@@ -133,7 +133,7 @@ while(no_sum_found && (length(input)>=(preamble_length + 1))) {
 # producing 62.
 #
 # What is the encryption weakness in your XMAS-encrypted list of numbers?
-# s
+#
 # 09-02 -------------------------------------------------------------------
 
 # input <- test_input

js/09.js

@@ -0,0 +1,67 @@
+var fs = require("fs")
+var combn = require('generatorics') // npm install generatorics
+
+Array.prototype.accumulate = function(ƒ) {
+  res = [this[0]]
+  for (var idx=1; idx<this.length; idx++) res.push(ƒ(res[idx - 1], this[idx]))
+  return(res)
+}
+
+// 09-01
+
+input = fs.readFileSync("../input/09-01.txt", "utf-8")
+          .split("\n")
+          .map((x) => parseInt(x))
+
+//input = [ 35, 20, 15, 25, 47, 40, 62, 55, 65, 95, 102, 117, 150, 182, 127, 219, 299, 277, 309, 576 ]
+
+preamble_length = 25
+input_start = preamble_length
+condition = true
+
+while(condition && (input.length > (preamble_length))) {
+
+  for (var pair of combn.combination([...Array(preamble_length).keys()], 2)) {
+    condition = (input[pair[0]] + input[pair[1]]) == input[input_start]
+    if (condition) break
+  }
+
+  if (condition) input.shift()
+
+}
+
+invalid = input[input_start]
+
+console.log(invalid)
+// 09-02
+
+input = fs.readFileSync("../input/09-01.txt", "utf-8")
+          .split("\n")
+          .map((x) => parseInt(x))
+
+//input = [ 35, 20, 15, 25, 47, 40, 62, 55, 65, 95, 102, 117, 150, 182, 127, 219, 299, 277, 309, 576 ]
+
+const cumsum = (sum => value => sum += value)(0)
+
+for (var idx=0; idx<input.length; idx++) {
+
+  csum = input.slice(idx, input.length).accumulate((a, b) => a + b)
+
+  if (csum.includes(invalid)) break // 'invalid' comes from part 1
+
+}
+
+rng = input.slice(idx, idx+csum.indexOf(invalid))
+
+console.log(Math.min(...rng) + Math.max(...rng))
+
+
+
+
+
+
+
+
+
+
+