diff --git a/2020/19/example b/2020/19/example
new file mode 100644
index 0000000..1500b6f
--- /dev/null
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diff --git a/2020/19/example.2 b/2020/19/example.2
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diff --git a/2020/19/input b/2020/19/input
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--- /dev/null
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+aabaabbbaaaaabbaaabaabbbaaaaababababaabbbbbabaab
+abbabbaabbbbbabaababaabbbbabbbab
+aabaaabbbaabbaabbaabbabb
+aabbaaabbaabaababbbabbab
+aabbbababaaabababbbbaabbababbbbbaaaabbab
+baababbaaabaaababaaaabbbbbabaaaabbbabbba
+bbaaaaabbabaabaaaaaabbba
+baabbaababaaaabbaaabbaaaaabababaababaabaabbbaabaaabababbbbabbbbbbabbbbaaaaaabbbbbaaaaaaa
+abbbabbaaaaabaaabbbbaaaaaabbaaabaabbbababbbbbababbababbbabaaabbaabbaabaabbababbaaabbbbbbaabbaabb
+bbbaaaabaabababaabbbbaba
+aaabaaababaaabbbaabbabbb
+ababaaabbaabaabbbbbaaaaaaaabbaaa
+abbbbbaabbaaaaaabbbaaabb
+bbaaababbabbaabbaabaabaababbaabaaababbab
+abbabaababaabbabbabaabbbaaaabbbbbaabbaababaaabba
+bbbbbbabbaaaaababababbba
+aaaabaabbbabaabbbbbabaaa
+baaaabbbbaaaaaabbabbbbaaabaababbaaaaaaab
+aaaaaabbbbbbaaaaaabbabababbbbaabababbbaa
+aabbbbbabaabbaabaaaaabbaabbabaaabbababaabbbbbaababbababa
+aaaaaabbbaaaabbabbbabbaa
+aababaabbbaaaaabbbbbabba
+bbaaaaaaaaaaabbbbbbbaaaa
+babbbbabaabbaaaabbaabbab
+babbaababaabaabbbabbbababaaaabbabbbbaabbbbbbaaaa
+bbaabbbbbabaabaabbabaaaa
+ababbbbaaaabaabbbbabbabaabbababa
+baabaabbabbaabbbbbababba
+aabbaabbaabbaababbaabaab
+ababaaabbabaaaaaaaaaabaa
+baabaabbbbaabbbbbbaaaaba
+bbbababbbbbabababbbabaabbabaaababaabbaaabbabbbabbbababab
+abbbaaaaaaaaabaabbabbbbb
+bbbaabbbabbababbbaababaabaaaabaaaaaaabaa
+ababbbbababbbbababbbabba
+aaaaababbbaabababbabbbaa
+aaaaaabbabaaabaababaabaababaabba
+babaaaabababbababbbaaaaaabbaabbbaaaabbab
+bbbbaaaababaaabababaabba
+abbbaabaaaaabbbbabbababa
+bbbbabbbbbaababbbabababb
+aaaabbaabbbaabbbabbbaaaa
+aabaabbabbbbbbaaaaabbaaa
+abbaaabbbaaaababaaababbaaaaabaaaaaaabbab
+abbaaaaaaaaabaaaababaaabbbaaabaa
+ababaabaaabbabaabbbbaaba
+bbbbabbbabbabaabbbbabbba
diff --git a/2020/19/solution1.js b/2020/19/solution1.js
new file mode 100644
index 0000000..28ee2cd
--- /dev/null
+++ b/2020/19/solution1.js
@@ -0,0 +1,48 @@
+const fs = require("fs");
+
+let [rules, messages] = fs
+  .readFileSync("input", "utf-8")
+  .trim()
+  .split("\n\n")
+  .map((part) => part.split("\n"));
+
+rules = rules
+  .map((line) => line.split(": "))
+  .map(([num, rule]) => [parseInt(num), rule])
+  .sort((a, b) => a[0] - b[0])
+  .map(([_, rule]) => rule);
+
+console.log(rules);
+
+console.log("=");
+// console.log(messages);
+
+function getRegex(idx) {
+  const rule = rules[idx];
+  if (rule.startsWith('"')) {
+    return rule.slice(1, rule.length - 1);
+  }
+  let regex = "";
+  let multiple = false;
+  for (const symbol of rule.split(" ")) {
+    if (symbol === "|") {
+      regex = "(" + regex + "|";
+      multiple = true;
+    } else {
+      regex = regex + getRegex(parseInt(symbol));
+    }
+  }
+  regex = multiple ? regex + ")" : regex;
+  rules[idx] = '"' + regex + '"';
+  return regex;
+}
+
+const regex = new RegExp(`^${getRegex(0)}$`);
+console.log(rules);
+console.log(regex);
+
+let sum = 0;
+for (const message of messages) {
+  if (regex.test(message)) sum++;
+}
+console.log(sum);
diff --git a/2020/19/solution2.js b/2020/19/solution2.js
new file mode 100644
index 0000000..5dabf48
--- /dev/null
+++ b/2020/19/solution2.js
@@ -0,0 +1,73 @@
+const fs = require("fs");
+
+let [rules, messages] = fs
+  .readFileSync("input", "utf-8")
+  .trim()
+  .split("\n\n")
+  .map((part) => part.split("\n"));
+
+rules = Object.fromEntries(rules.map((line) => line.split(": ")));
+
+// unecessary, but might reveal an overlooked loop
+rules["8"] = "42 | 42 8";
+rules["11"] = "42 31 | 42 11 31";
+
+// console.log(rules);
+// console.log(messages);
+
+function getRegex(idx, visited = []) {
+  const rule = rules[idx];
+  if (rule.startsWith('"')) {
+    return rule.slice(1, rule.length - 1);
+  }
+  let regex = "";
+  let multiple = false;
+  for (const symbol of rule.split(" ")) {
+    if (symbol === "|") {
+      regex = "(" + regex + "|";
+      multiple = true;
+    } else {
+      regex = regex + getRegex(parseInt(symbol), visited.concat(idx));
+    }
+  }
+  regex = multiple ? regex + ")" : regex;
+  rules[idx] = '"' + regex + '"';
+  return regex;
+}
+
+// Rule 0 is "8 11"
+// These rules are the only looping rules through self referencing
+// rule 8: 42 | 42 8
+//   expects rule 42 one or more times
+// rule 11: 42 31 | 42 11 31
+//   recursively expects R42 R11 R31
+//   translated:
+//   expects rule 42 one or more times followed by 31 by the same quantity
+// combined:
+//   rule 0: 8 11
+//   start of string matches 42 (one or more)
+//   end of string matches 31 (one or more)
+//   the quantity of R42 matches has to be more than the quantity of R31
+
+const rule42 = getRegex(42);
+const rule31 = getRegex(31);
+const possibleEndings = [];
+
+// 10 is a guessed maximum repetition based message length
+// if this value is too high the regex wont compile
+// for larger messages a recursive approach is necessary
+for (let reps = 1; reps <= 10; reps++) {
+  possibleEndings.push(`((${rule42.repeat(reps)})(${rule31.repeat(reps)}))`);
+}
+const patternRaw = `^(${rule42})+(${possibleEndings.join("|")})$`;
+// console.log("Pattern:", patternRaw);
+console.log("Compiling RegExp...");
+const pattern = new RegExp(patternRaw);
+console.log("done.");
+
+console.log("Checking messages...");
+let sum = 0;
+for (let message of messages) {
+  if (pattern.test(message)) sum++;
+}
+console.log(sum);