Given an integer, write a function to determine if it is a power of two.
一行解決戰鬥:
return n > 0 && (n & (n - 1)) == 0;
Given an integer, write a function to determine if it is a power of two.
一行解決戰鬥:
return n > 0 && (n & (n - 1)) == 0;
翻轉一棵二叉樹。 示例: 輸入: 4 / \ 2 7 / \ / \ 1 3 6 9 輸出: 4 / \ 7 2 / \ / \ 9 6