All but Blogging

1 files changed, 51 insertions, 0 deletions

diff --git a/challenge-119/dave-jacoby/node/ch-2.js b/challenge-119/dave-jacoby/node/ch-2.js
new file mode 100644
index 0000000000..7386e2a0db
--- /dev/null
+++ b/challenge-119/dave-jacoby/node/ch-2.js
@@ -0,0 +1,51 @@
+"use strict";
+
+// let list = Array(20).fill();
+// for (let i in list) {
+//   let j = first_pass(i);
+//   let s = get_sequence(i * 2);
+//   let v = solve_sequence(i);
+//   console.log(["", "i", i, "j", j, "v", v].join("\t"));
+// }
+
+let list = [2, 5, 10, 60, 200];
+
+for (let i in list) {
+  let n = list[i];
+  let s = solve_sequence(n);
+  console.log(["", n, s].join("\t"));
+}
+
+function solve_sequence(n) {
+  let j = n * 2;
+  let s = get_sequence(1 + j);
+  while (s[n] == undefined) {
+    j = j * 2;
+    s = get_sequence(j);
+  }
+  return s[n];
+}
+
+function get_sequence(n) {
+  n = parseInt(n);
+  let sequence = Array(n)
+    .fill("")
+    .map((x, i) => first_pass(i + 1))
+    .filter((x) => !x.toString().match(/0/))
+    .filter((x) => !x.toString().match(/11/));
+  sequence.unshift(0);
+  return sequence;
+}
+
+function first_pass(n) {
+  if (n == 0) {
+    return 0;
+  }
+  let output = [];
+  while (n) {
+    let i = n % 4;
+    n = parseInt(n / 4);
+    output.push(i);
+  }
+  return output.reverse().join("");
+}