1 files changed, 52 insertions, 0 deletions
diff --git a/2020/08/solve.js b/2020/08/solve.js
new file mode 100644
index 0000000..c03edcb
--- /dev/null
+++ b/2020/08/solve.js
@@ -0,0 +1,52 @@
+const fs = require("fs");
+const data = fs.readFileSync("input", "utf8").split('\n');
+
+function run(code)
+{
+    let acc = 0;
+    let visited = [];
+
+    let i = 0;
+    while (!visited.includes(i)) {
+        visited.push(i);
+        if (!code[i])
+            return { acc, i };
+
+        const [op, cnt] = code[i].split(" ");;
+        switch (op) {
+            case "acc":
+                acc += +cnt;
+                break;
+            case "jmp":
+                i += +cnt - 1;
+                break;
+            default:
+                break;
+        }
+        i++;
+    }
+    return { acc, i };
+}
+
+function partOne()
+{
+    return run(data).acc;
+}
+
+function partTwo()
+{
+    for (let i = 0; i < data.length; i++) {
+        const [op, cnt] = data[i].split(" ");;
+        if (op == "acc")
+            continue; // Skip correction
+
+        let fixed = [...data];
+        fixed.splice(i, 1, `${op == "nop" ? "jmp" : "nop"} ${cnt}`);
+        let results = run(fixed);
+        if (results.i == fixed.length)
+            return results.acc;
+    }
+}
+
+console.log(partOne());
+console.log(partTwo());