654. 最大二叉树-TS版【中等题】

题目链接

class TreeNode {
    val: number
    left: TreeNode | null
    right: TreeNode | null
    constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
        this.val = (val===undefined ? 0 : val)
        this.left = (left===undefined ? null : left)
        this.right = (right===undefined ? null : right)
    }
}

function constructMaximumBinaryTree(nums: number[]): TreeNode | null {
    if (!nums.length) return null;
    if (nums.length === 1) return new TreeNode(nums[0]);
    const maxVal = Math.max(...nums);
    const maxIndex = nums.findIndex(it => it === maxVal);
    const leftRoot = constructMaximumBinaryTree(nums.slice(0, maxIndex));
    const rightRoot = constructMaximumBinaryTree(nums.slice(maxIndex+1,nums.length));
    return new TreeNode(maxVal, leftRoot, rightRoot);
};


// 验证代码
(()=>{
    console.log('constructMaximumBinaryTree', constructMaximumBinaryTree([3,2,1,6,0,5]));
    console.log('constructMaximumBinaryTree', constructMaximumBinaryTree([3,2,1]));
})();