public class TreeNode {
public int val;
public TreeNode left;
public TreeNode right;
public TreeNode(int x) {
val = x;
}
public TreeNode(int x, TreeNode left, TreeNode right) {
this.val = x;
this.left = left;
this.right = right;
}
// public static TreeNode buildTree(Integer... array) {
// Integer[] s = new Integer[array.length];
// for (int i = 0; i < array.length; i++) {
// s[i] = array[i];
// }
// return buildTree(s);
// }
/**
* 建立完全二叉树
*/
public static TreeNode buildTree(Integer[] array) {
TreeNode[] nodes = new TreeNode[array.length];
for (int i = array.length - 1; i >= 0; i--) {
nodes[i] = array[i] == null ? null : new TreeNode(array[i]);
if (2 * i + 1 < array.length) {
nodes[i].left = nodes[2 * i + 1];
}
if (2 * i + 2 < array.length) {
nodes[i].right = nodes[2 * i + 2];
}
}
return nodes[0];
}
}