leetcode78回溯算法子集

huang · huang · commit 6771d0709f62 · 2019-11-08T00:43:57.000+08:00
diff --git a/leetcode/Subsets0078.java b/leetcode/Subsets0078.java
@@ -0,0 +1,39 @@
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * leetcode���ݷ����Ӽ�
+ * ����Ƚ��ѣ������㷨�ľ�������ƽ������ĸ���Դ��ģ�
+ */
+
+ public class Subsets0078{
+
+    public static void main(String[] args) {
+        int nums[] = {1,2,3};
+        subsets(nums);
+    }
+
+    private static List<List<Integer>> result = new ArrayList<List<Integer>>();
+
+    public static List<List<Integer>> subsets(int[] nums) {
+        
+        List<Integer> tmp = new ArrayList<>();
+        backtrack(nums, 0, tmp);
+        return result;
+    }
+
+    private static void backtrack(int[] nums, int start, List<Integer> tmp) {
+
+        result.add(new ArrayList<>(tmp));
+
+        for (int i = start; i < nums.length; i++) {
+            tmp.add(nums[i]);
+            backtrack(nums, i+1, tmp);
+            tmp.remove(tmp.size()-1);
+        }
+        for (int j : tmp) {
+            System.out.print(j + " ");
+        }
+        System.out.println();
+    }
+ }
