add 100, 231

Author: rustykitty

0100-same-tree.cpp

@@ -0,0 +1,28 @@
+/*
+100. Same Tree
+
+Submitted: December 9, 2024
+
+Runtime: 0 ms (beats 100.00%)
+Memory: 12.76 MB (beats 15.77%)
+*/
+
+/**
+ * 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:
+    bool isSameTree(TreeNode* p, TreeNode* q) {
+        if (p == nullptr || q == nullptr) return p == q;
+        if (p->val != q->val) return false;
+        return isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
+    }
+};

0231-power-of-two.cpp

@@ -0,0 +1,16 @@
+/*
+231. Power of Two
+
+Solved: December 9, 2024
+
+Runtime: 0 ms (beats 100.00%)
+Memory: 7.84 MB (beats 10.33%)
+*/
+
+class Solution {
+public:
+    bool isPowerOfTwo(int n) {
+        if (n <= 0) return false;
+        return !(n & (n - 1));
+    }
+};