Create 0040-combination-sum-ii.swift

Author: drxlx

swift/0040-combination-sum-ii.swift

@@ -0,0 +1,33 @@
+class Solution {
+    func combinationSum2(_ candidates: [Int], _ target: Int) -> [[Int]] {
+        var candidates = candidates.sorted()
+        var res = [[Int]]()
+        var cur = [Int]()
+        var total = 0
+
+        func dfs(_ i: Int) {
+            var i = i
+            if total == target {
+                res.append(cur)
+                return
+            }
+            if total > target || i == candidates.count {
+                return
+            }
+
+            cur.append(candidates[i])
+            total += candidates[i]
+            dfs(i + 1)
+            cur.popLast()
+            total -= candidates[i]
+            while i + 1 < candidates.count && candidates[i] == candidates[i + 1] {
+                i += 1
+            }
+            dfs(i + 1)
+        }
+
+        dfs(0)
+
+        return res
+    }
+}