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diff --git a/day4/package.json b/day4/package.json
new file mode 100644
index 0000000..29c5523
--- /dev/null
+++ b/day4/package.json
@@ -0,0 +1,5 @@
+{
+  "devDependencies": {
+    "@types/node": "^18.11.10"
+  }
+}
diff --git a/day4/solution.ts b/day4/solution.ts
new file mode 100644
index 0000000..9479255
--- /dev/null
+++ b/day4/solution.ts
@@ -0,0 +1,32 @@
+import { readFileSync } from 'fs';
+import { join } from 'path';
+
+const range = (start, end) => Array.from(Array(end - start + 1).keys()).map(x => x + start);
+
+const fileString = readFileSync(join(__dirname, "input"), 'utf-8');
+const data = fileString.split("\n");
+
+var overlaping: number = 0;
+var anyOverlaping: number = 0;
+
+for (const pair of data) {
+  const elves = pair.split(",");
+  if (elves.length != 2) {
+    continue;
+  }
+  const e1 = elves[0].split("-");
+  const e2 = elves[1].split("-");
+  const e1r = range(+e1[0], +e1[1]);
+  const e2r = range(+e2[0], +e2[1]);
+
+  if (e1r.every(val => e2r.includes(val)) || e2r.every(val => e1r.includes(val))) {
+    overlaping += 1;
+  }
+
+  if (e1r.some(val => e2r.includes(val))) {
+    anyOverlaping += 1;
+  }
+}
+
+console.log(overlaping);
+console.log(anyOverlaping);
diff --git a/day4/tsconfig.json b/day4/tsconfig.json
new file mode 100644
index 0000000..80c821c
--- /dev/null
+++ b/day4/tsconfig.json
@@ -0,0 +1,7 @@
+{
+  "compilerOptions": {
+    "types": [
+      "node"
+    ]
+  }
+}