Update 0046.全排列.md

problems/0046.全排列.md

@@ -147,6 +147,30 @@ public:
 
 
 Java：
+class Solution {
+	List<List<Integer>> result=new ArrayList<List<Integer>>();
+	Deque<Integer> path=new LinkedList<Integer>();
+	void backtracking(int []nums,Boolean []used) {
+		if(path.size()==nums.length) {
+			result.add(new ArrayList<Integer>(path));
+			return;
+		}
+		for(int i=0;i<nums.length;i++) {
+			if(used[i]) continue;
+			used[i]=true;
+			path.addLast(nums[i]);
+			backtracking(nums, used);
+			used[i]=false;
+			path.pollLast();
+		}
+	}
+    public List<List<Integer>> permute(int[] nums) {
+    	Boolean []used=new Boolean[nums.length];
+    	for(int i=0;i<used.length;i++) used[i]=false;
+    	backtracking(nums, used);
+    	return result;
+    }
+}
 
 
 Python：