Added 7th solution

1 files changed, 49 insertions, 0 deletions

diff --git a/2020/7/solve.js b/2020/7/solve.js
new file mode 100644
index 0000000..28359e6
--- /dev/null
+++ b/2020/7/solve.js
@@ -0,0 +1,49 @@
+const fs = require("fs");
+const data = fs.readFileSync("input", "utf8").split('\n');
+
+function getMap()
+{
+    return data.reduce((map, line) => {
+        const [superBag, subBags] = line.split(" contain ");
+        const bag = superBag.split(" ").slice(0, -1).join(" ");
+        if (!subBags || subBags == "no other bags.") {
+            map[bag] = {};
+        } else {
+            map[bag] = subBags.split(", ").reduce((subMap, bags) => {
+                const subBag = bags.split(" ");
+                const subBagName = subBag.slice(1, -1).join(" ");
+                subMap[subBagName] = +subBag[0];
+                return subMap;
+            }, {});
+        }
+        return map;
+    }, {});
+}
+
+function inBag(map, superBag, subBag)
+{
+    if (map[superBag][subBag])
+        return true;
+
+    return Object.keys(map[superBag]).reduce((acc, key) => acc || inBag(map, key, subBag), false);
+}
+
+function countBags(map, bag)
+{
+    return Object.keys(map[bag]).reduce((acc, key) => acc + map[bag][key] * (1 + countBags(map, key)), 0);
+}
+
+function partOne()
+{
+    const map = getMap();
+    return Object.keys(map).reduce((n, key) => n + inBag(map, key, "shiny gold"), 0);
+}
+
+function partTwo()
+{
+    const map = getMap();
+    return countBags(map, "shiny gold");
+}
+
+console.log(partOne());
+console.log(partTwo());