add 97

Author: luliyucoordinate

README.md

@@ -76,6 +76,7 @@ LeetCode
 |0094|[Binary Tree Inorder Traversal](https://leetcode.com/problems/binary-tree-inorder-traversal/) | c | [c++](./src/0094-Binary-Tree-Inorder-Traversal/0094.cpp) |[python](./src/0094-Binary-Tree-Inorder-Traversal/0094.py)|||Medium|
 |0095|[Unique Binary Search Trees II](https://leetcode.com/problems/unique-binary-search-trees-ii/) | c | [c++](./src/0095-Unique-Binary-Search-Trees-II/0095.cpp) |[python](./src/0095-Unique-Binary-Search-Trees-II/0095.py)|||Medium|
 |0096|[Unique Binary Search Trees](https://leetcode.com/problems/unique-binary-search-trees/) | c | [c++](./src/0096-Unique-Binary-Search-Trees/0096.cpp) |[python](./src/0096-Unique-Binary-Search-Trees/0096.py)|||Medium|
+|0097|[Interleaving String](https://leetcode.com/problems/interleaving-string/) | c | [c++](./src/0097-Interleaving-String/0097.cpp) |[python](./src/0097-Interleaving-String/0097.py)|||Medium|
 |0098|[Validate Binary Search Tree](https://leetcode.com/problems/validate-binary-search-tree/) | c | [c++](./src/0098-Validate-Binary-Search-Tree/0098.cpp) |[python](./src/0098-Validate-Binary-Search-Tree/0098.py)|||Medium|
 |0100|[Same Tree](https://leetcode.com/problems/same-tree/) | c | [c++](./src/0100-Same-Tree/0100.cpp) |[python](./src/0100-Same-Tree/0100.py)|||Easy|
 |0102|[Binary Tree Level Order Traversal](https://leetcode.com/problems/binary-tree-level-order-traversal/) | c | [c++](./src/0102-Binary-Tree-Level-Order-Traversal/0102.cpp) |[python](./src/0102-Binary-Tree-Level-Order-Traversal/0102.py)|||Medium|

src/0097-Interleaving-String/0097.cpp

@@ -0,0 +1,26 @@
+#include <deque>
+#include <string>
+using namespace std;
+
+static int x = []() {std::ios::sync_with_stdio(false); cin.tie(0); return 0; }();
+class Solution 
+{
+public:
+    bool isInterleave(string s1, string s2, string s3) 
+    {
+        if (s1.size() + s2.size() != s3.size()) return false;
+        deque<deque<bool>> mem(s1.size() + 1, deque<bool>(s2.size() + 1, false));
+        for (int i = 0; i <= s1.size(); ++i)
+        {
+            for (int j = 0; j <= s2.size(); ++j)
+            {
+                if (i == 0 and j == 0) mem[i][j] = true;
+                else if (i == 0) mem[i][j] = mem[i][j - 1] and (s2[j - 1] == s3[i + j - 1]);
+                else if (j == 0) mem[i][j] = mem[i - 1][j] and (s1[i - 1] == s3[i + j - 1]);
+                else mem[i][j] = (mem[i][j - 1] and (s2[j - 1] == s3[i + j - 1])) or (
+                                  mem[i - 1][j] and (s1[i - 1] == s3[i + j - 1]));
+            }
+        }
+        return mem[s1.size()][s2.size()];
+    }
+};

src/0097-Interleaving-String/0097.py

@@ -0,0 +1,32 @@
+class Solution:
+    def isInterleave(self, s1, s2, s3):
+        """
+        :type s1: str
+        :type s2: str
+        :type s3: str
+        :rtype: bool
+        """
+        def helper(i, j, k, mem):
+            if (i, j) in mem:
+                return mem[(i, j)]
+            
+            if k == len(s3):
+                return True
+            
+            if i < len(s1) and s1[i] == s3[k]:
+                if (helper(i+1, j, k + 1, mem)):
+                    mem[(i, j)] = True
+                    return True
+                
+            if j < len(s2) and s2[j] == s3[k]:
+                if helper(i, j+1, k+1, mem):
+                    mem[(i, j)] = True
+                    return True
+                
+            mem[(i, j)] = False
+            return False
+        
+        if len(s1)+len(s2) != len(s3):
+            return False
+        
+        return helper(0, 0, 0, {})