add Subsets II

js/subsets/README.md

@@ -9,8 +9,7 @@ Note: The solution set must not contain duplicate subsets.
 For example,
 If nums = [1,2,3], a solution is:
 
-
-
+```
 [
   [3],
   [1],
@@ -21,3 +20,5 @@ If nums = [1,2,3], a solution is:
   [1,2],
   []
 ]
+
+```

js/subsetsIi/README.md

@@ -0,0 +1,22 @@
+## Subsets II 
+link: <https://leetcode.com/problems/subsets-ii/>
+
+Given a collection of integers that might contain duplicates, nums, return all possible subsets.
+
+Note: The solution set must not contain duplicate subsets.
+
+
+For example,
+If nums = [1,2,2], a solution is:
+
+
+```
+[
+  [2],
+  [1],
+  [1,2,2],
+  [2,2],
+  [1,2],
+  []
+]
+```

js/subsetsIi/subsets-ii.js

@@ -0,0 +1,39 @@
+/**
+ * @param {number[]} nums
+ *  @return {number[][]}
+ **/
+var subsetsWithDup = function(nums) {
+  return getSolutions(nums, []).concat([[]]);
+};
+
+function getSolutions(nums, list) {
+  if (nums.length === 0) {
+    return [];
+  }
+
+  var resNext = getSolutions(nums.slice(1), list);
+
+  var res = [];
+  var current = nums[0];
+  if (list.indexOf(current) === -1) {
+    list.push(current);
+    res.push([current]);
+  }
+
+  res = [].concat(resNext, res);
+
+  // n and n - 1
+  for (var i = 0; i < resNext.length; i++) {
+    var val = resNext[i];
+    res.push([].concat(current, val));
+  }
+
+  return res;
+}
+
+console.log(subsetsWithDup([1, 2, 2]))
+
+var eq = require('assert').deepEqual;
+eq(subsetsWithDup([1, 2, 2]), [[2], [1], [1,2,2], [2,2], [1,2], []]);
+
+eq(subsetsWithDup([1, 1, 2, 2]), [[],[1],[1,1],[1,1,2],[1,1,2,2],[1,2],[1,2,2],[2],[2,2]]);