add 78-Subsets

javascript/78-Subsets.js

@@ -0,0 +1,20 @@
+function subsets(nums) {
+  let res = [];
+  let subset = [];
+  function dfs(i) {
+    if (i >= nums.length) {
+      res.push(subset.slice());
+      return;
+    }
+
+    subset.push(nums[i]);
+    dfs(i + 1);
+
+    subset.pop();
+    dfs(i + 1);
+  }
+
+  dfs(0);
+
+  return res;
+}