@@ -0,0 +1,31 @@
+let ternarySearch = (arr, start, end, key) => {
+
+    if (start >= end) {
+        return -1;
+    }
+
+    let midFirst = start + Math.floor((end - start) / 3);
+    let midSecond = midFirst + Math.floor((end - start) / 3);
+
+    if (arr[midFirst] === key) {
+        return midFirst;
+    }
+    if (arr[midSecond] === key) {
+        return midSecond;
+    }
+
+    if (key < arr[midFirst]) {
+        return ternarySearch(arr, start, midFirst - 1, key);
+    }
+
+    if (key > arr[midSecond]) {
+        return ternarySearch(arr, midFirst + 1, end, key);
+    }
+
+    else {
+        return ternarySearch(arr, midFirst + 1, midSecond - 1, key);
+    }
+};
+
+const arr = [1,6,9,17,21,69,85,100];
+console.log(ternarySearch(arr, 0, arr.length, 1));