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Author: xuebu

.DS_Store

@@ -0,0 +1,9 @@
+class Solution {
+    public int[] constructRectangle(int area) {
+        int sqrt = (int) Math.sqrt(area);
+        while (area % sqrt != 0) {
+            sqrt--;
+        }
+        return new int[]{area / sqrt, sqrt};
+    }
+}

math/construct-the-rectangle-492.java

@@ -0,0 +1,11 @@
+class Solution {
+    public boolean flipEquiv(TreeNode root1, TreeNode root2) {
+        return isEqual(root1,root2);
+    }
+    public boolean isEqual(TreeNode root1,TreeNode root2){
+        if (root1 == null && root2 == null) return true;
+        if ( (root1 == null && root2 != null) || (root1 != null && root2 == null) || (root1.val!=root2.val) ) return false;
+        return isEqual(root1.left,root2.right)&&isEqual(root1.right,root2.left)
+            ||isEqual(root1.left,root2.left)&&isEqual(root1.right,root2.right);
+    }
+}