Create combinations.js

Create combinations.js

Author: PranamBhat

JavaScript/combinations.js

@@ -0,0 +1,29 @@
+/**
+ * @param {number} n
+ * @param {number} k
+ * @return {number[][]}
+ */
+
+var combine = function(n, k) {
+  if (n < k || k < 1) return [];
+
+  var res = [];
+
+  helper(res, [], 0, n, k);
+
+  return res;
+};
+
+var helper = function (res, now, start, n, k) {
+  if (k === 0) {
+    res.push(Array.from(now));
+    return;
+  }
+
+  for (var i = start; i < n; i++) {
+    now.push(i + 1)
+    helper(res, now, i + 1, n, k - 1);
+    now.pop();
+  }
+    
+};