leetcode-problemset/leetcode-cn/problem (English)/使二进制数组全部等于 1 的最少操作次数 II(English) [minimum-operations-to-make-binary-array-elements-equal-to-one-ii].html

<p>You are given a <span data-keyword="binary-array">binary array</span> <code>nums</code>.</p>

<p>You can do the following operation on the array <strong>any</strong> number of times (possibly zero):</p>

<ul>
	<li>Choose <strong>any</strong> index <code>i</code> from the array and <strong>flip</strong> <strong>all</strong> the elements from index <code>i</code> to the end of the array.</li>
</ul>

<p><strong>Flipping</strong> an element means changing its value from 0 to 1, and from 1 to 0.</p>

<p>Return the <strong>minimum</strong> number of operations required to make all elements in <code>nums</code> equal to 1.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">nums = [0,1,1,0,1]</span></p>

<p><strong>Output:</strong> <span class="example-io">4</span></p>

<p><strong>Explanation:</strong><br />
We can do the following operations:</p>

<ul>
	<li>Choose the index <code>i = 1</code><span class="example-io">. The resulting array will be <code>nums = [0,<u><strong>0</strong></u>,<u><strong>0</strong></u>,<u><strong>1</strong></u>,<u><strong>0</strong></u>]</code>.</span></li>
	<li>Choose the index <code>i = 0</code><span class="example-io">. The resulting array will be <code>nums = [<u><strong>1</strong></u>,<u><strong>1</strong></u>,<u><strong>1</strong></u>,<u><strong>0</strong></u>,<u><strong>1</strong></u>]</code>.</span></li>
	<li>Choose the index <code>i = 4</code><span class="example-io">. The resulting array will be <code>nums = [1,1,1,0,<u><strong>0</strong></u>]</code>.</span></li>
	<li>Choose the index <code>i = 3</code><span class="example-io">. The resulting array will be <code>nums = [1,1,1,<u><strong>1</strong></u>,<u><strong>1</strong></u>]</code>.</span></li>
</ul>
</div>

<p><strong class="example">Example 2:</strong></p>

<div class="example-block">
<p><strong>Input:</strong> <span class="example-io">nums = [1,0,0,0]</span></p>

<p><strong>Output:</strong> <span class="example-io">1</span></p>

<p><strong>Explanation:</strong><br />
We can do the following operation:</p>

<ul>
	<li>Choose the index <code>i = 1</code><span class="example-io">. The resulting array will be <code>nums = [1,<u><strong>1</strong></u>,<u><strong>1</strong></u>,<u><strong>1</strong></u>]</code>.</span></li>
</ul>
</div>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li>
	<li><code>0 &lt;= nums[i] &lt;= 1</code></li>
</ul>