add: java: 7-100

Author: poseidon-code

07-trees/00100-Same_Tree/00100-same_tree.java

@@ -0,0 +1,92 @@
+// 100: Same Tree
+// https://leetcode.com/problems/same-tree/
+
+import java.util.Queue;
+import java.util.ArrayList;
+import java.util.LinkedList;
+
+
+class Solution {
+    public static class TreeNode {
+        Integer val;
+        TreeNode left;
+        TreeNode right;
+        TreeNode() {}
+        TreeNode(Integer val) { this.val = val; }
+        TreeNode(Integer val, TreeNode left, TreeNode right) { this.val = val; this.left = left; this.right = right; }
+    }
+
+    public static class Tree {
+        TreeNode root;
+        Tree() { this.root = null; }
+    }
+
+    private static TreeNode creator(Integer[] values, TreeNode root, int i, int n) {
+        if (n==0) return null;
+        if (i<n) {
+            TreeNode temp = new TreeNode(values[i]);
+            root = temp;
+            root.left = creator(values, root.left, 2*i+1, n);
+            root.right = creator(values, root.right, 2*i+2, n);
+        }
+        return root;
+    }
+
+    public static void createTree(Tree tree, Integer[] inputs) {
+        tree.root = creator(inputs, tree.root, 0, inputs.length);
+    }
+
+    public static void showTree(TreeNode root) {
+        Queue<TreeNode> q = new LinkedList<>();
+        ArrayList<ArrayList<Integer>> result = new ArrayList<>();
+        ArrayList<Integer> c = new ArrayList<>();
+        if (root == null) { System.out.println("Empty !"); return; }
+        q.add(root);
+        q.add(null);
+        while (!q.isEmpty()) {
+            TreeNode t = q.poll();
+            if (t==null) {
+                result.add(c);
+                c = new ArrayList<>();
+                if (q.size() > 0) q.add(null);
+            } else {
+                c.add(t.val);
+                if (t.left!=null) q.add(t.left);
+                if (t.right!=null) q.add(t.right);
+            }
+        }
+
+        System.out.print("["); for (var x : result) {
+            System.out.print("["); for (var y : x) {
+                if (y==null) { System.out.print("NULL,"); continue; }
+                System.out.print(y+",");
+            } System.out.print("\b],");
+        } System.out.println("\b]");
+    }
+
+
+    // SOLUTION
+    public boolean isSameTree(TreeNode p, TreeNode q) {
+        if (p == null && q == null) return true;
+        if (p == null || q == null) return false;
+        if (p.val != q.val) return false;
+        return isSameTree(p.left, q.left) && isSameTree(p.right, q.right);
+    }
+
+
+    public static void main(String[] args) {
+        Solution o = new Solution();
+        Tree p = new Tree();
+        Tree q = new Tree();
+
+        // INPUT
+        Integer[] pn = {1,2,3};
+        createTree(p, pn);
+        Integer[] qn = {1,2,3};
+        createTree(q, qn);
+
+        // OUTPUT
+        var result = o.isSameTree(p.root, q.root);
+        System.out.println(result);
+    }
+}