https://leetcode.cn/problems/minimum-operations-to-make-binary-array-elements-equal-to-one-i/solution/tan-xin-tvzhi-mian-dui-guo-liao-zhe-cun-94o4e/
往右遍历只改零会减少问题规模且和上一步是同一类问题
文中说明了是最简的，可我有新问题是如何证明最简下能判断出不能转化成全是1
https://leetcode.cn/problems/minimum-operations-to-make-binary-array-elements-equal-to-one-i/solution/cong-zuo-dao-you-xiu-gai-pythonjavacgo-b-k38u/
茶佬已答
