添加 0040.组合总和II.md Scala版本

problems/0040.组合总和II.md

@@ -693,5 +693,37 @@ func combinationSum2(_ candidates: [Int], _ target: Int) -> [[Int]] {
 }
 ```
 
+
+## Scala
+
+```scala
+object Solution {
+  import scala.collection.mutable    
+  def combinationSum2(candidates: Array[Int], target: Int): List[List[Int]] = {
+    var res = mutable.ListBuffer[List[Int]]()
+    var path = mutable.ListBuffer[Int]()
+    var candidate = candidates.sorted
+
+    def backtracking(sum: Int, startIndex: Int): Unit = {
+      if (sum == target) {
+        res.append(path.toList)
+        return
+      }
+
+      for (i <- startIndex until candidate.size if sum + candidate(i) <= target) {
+        if (!(i > startIndex && candidate(i) == candidate(i - 1))) {
+          path.append(candidate(i))
+          backtracking(sum + candidate(i), i + 1)
+          path = path.take(path.size - 1)
+        }
+      }
+    }
+
+    backtracking(0, 0)
+    res.toList
+  }
+}
+```
+
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