652

Author: tbswang

.vscode/settings.json

@@ -6,6 +6,14 @@
     "algorithm": "cpp",
     "string": "cpp",
     "queue": "cpp",
-    "chrono": "cpp"
+    "chrono": "cpp",
+    "unordered_map": "cpp",
+    "__functional_03": "cpp",
+    "__string": "cpp",
+    "deque": "cpp",
+    "functional": "cpp",
+    "system_error": "cpp",
+    "*.tcc": "cpp",
+    "array": "cpp"
   }
 }

652.寻找重复的子树.cpp

@@ -0,0 +1,86 @@
+/*
+ * @lc app=leetcode.cn id=652 lang=cpp
+ *
+ * [652] 寻找重复的子树
+ */
+
+#include <iostream>
+#include <vector>
+#include <unordered_map>
+#include <string>
+#include <sstream>
+using namespace std;
+struct TreeNode
+{
+    int val;
+    TreeNode *left;
+    TreeNode *right;
+    TreeNode() : val(0), left(nullptr), right(nullptr) {}
+    TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
+    TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
+};
+
+// @lc code=start
+/**
+ * Definition for a binary tree node.
+ * struct TreeNode {
+ *     int val;
+ *     TreeNode *left;
+ *     TreeNode *right;
+ *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
+ *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
+ * };
+ */
+class Solution
+{
+public:
+    unordered_map<string, int> memo;
+    vector<TreeNode *> res;
+    vector<TreeNode *> findDuplicateSubtrees(TreeNode *root)
+    {
+        find(root);
+        return res;
+    }
+    string find(TreeNode *root)
+    {
+        if (root == nullptr)
+            return "#";
+
+        string left = find(root->left);
+        string right = find(root->right);
+        string subTree = left + "," + right + "," + int_string(root->val);
+
+        int freq = memo[subTree];
+        if (freq == 1)
+        {
+            res.push_back(root);
+            // cout << ">>>" << root->val;
+        }
+        memo[subTree] = freq + 1;
+        // cout << memo[subTree];
+        // cout << subTree << endl;
+        return subTree;
+    }
+    string int_string(int a)
+    { //int转string
+        stringstream st;
+        st << a;
+        string str = st.str();
+        return str;
+    }
+};
+// @lc code=end
+
+int main()
+{
+    Solution s;
+}
+/**
+ * 
+in 431 432 4
+先序遍历 124 324 4
+
+后序 42 42 4 3 1
+
+*/