Add leetcode 47.

1 files changed, 45 insertions, 0 deletions

diff --git a/leetcode/cpp/47.cpp b/leetcode/cpp/47.cpp
new file mode 100644
index 0000000..4a109ea
--- /dev/null
+++ b/leetcode/cpp/47.cpp
@@ -0,0 +1,45 @@
+#include <vector>
+#include <set>
+
+using std::vector;
+
+class Solution {
+public:
+
+    void DFS(int length, const std::vector<int>& nums, std::vector<int>& visited, std::vector<int>& current, std::vector<std::vector<int>>& result) {
+        if (length == 0) {
+            result.push_back(current);
+        }
+
+        int used[21] {0};
+
+        int size = nums.size();
+
+        for (int i = 0; i < size; i++) {
+            if (visited[i]) {
+                continue;
+            }
+
+            visited[i] = 1;
+
+            int num = nums[i];
+
+            if (!used[num + 10]) {
+                current.push_back(nums[i]);
+                DFS(length - 1, nums, visited, current, result);
+                current.pop_back();
+                used[num + 10] = 1;
+            }
+
+            visited[i] = 0;
+        }
+    }
+
+    vector<vector<int>> permuteUnique(vector<int>& nums) {
+        std::vector<int> visited(nums.size());
+        std::vector<int> current;
+        std::vector<std::vector<int>> result;
+        DFS(nums.size(),nums, visited, current, result);
+        return result;
+    }
+};
\ No newline at end of file