Add pre and post order.

Author: crypt096

searching-algorithms/DFS/post-order.js

@@ -0,0 +1,12 @@
+const depthFirstSearch = (node, list) => {
+  if (node.left) {
+    depthFirstSearch(node.left, list);
+  }
+
+  if (node.right) {
+    depthFirstSearch(node.right, list);
+  }
+
+  list.push(node.value);
+  return list;
+}

searching-algorithms/DFS/pre-order.js

@@ -0,0 +1,13 @@
+const depthFirstSearch = (node, list) => {
+  list.push(node.value);
+  
+  if (node.left) {
+    depthFirstSearch(node.left, list);
+  }
+
+  if (node.right) {
+    depthFirstSearch(node.right, list);
+  }
+
+  return list;
+}