We need at least <code>n</code> seconds, and at most <code>sum(nums[i]) + n</code> seconds.

We can binary search the earliest second where all indices can be marked.

If there is an operation where we change <code>nums[changeIndices[i]]</code> to a non-negative value, it is best for it to satisfy the following constraints:<ul> <li><code>nums[changeIndices[i]]</code> should not be equal to <code>0</code>.</li> <li><code>nums[changeIndices[i]]</code> should be changed to <code>0</code>.</li> <li>It should be the first position where <code>changeIndices[i]</code> occurs in <code>changeIndices</code>.</li> <li>There should be another second, <code>j</code>, where <code>changeIndices[i]</code> will be marked. <code>j</code> is in the range <code>[i + 1, m]</code>.</li> </ul>

Let <code>time_needed = sum(nums[i]) + n</code>. To check if we can mark all indices at some second <code>x</code>, we need to make <code>time_needed <= x</code>, using non-negative change operations as described previously.

Using a non-negative change operation on some <code>nums[changeIndices[i]]</code> that satisfies the constraints described previously reduces <code>time_needed</code> by <code>nums[changeIndices[i]] - 1</code>. So, we need to maximize the sum of <code>(nums[changeIndices[i]] - 1)</code> while ensuring that the non-negative change operations still satisfy the constraints.

Maximizing the sum of <code>(nums[changeIndices[i]] - 1)</code> can be done greedily using a min-priority queue and going in reverse starting from second <code>x</code> to second <code>1</code>, maximizing the sum of the values in the priority queue and ensuring that for every non-negative change operation on <code>nums[changeIndices[i]]</code> chosen, there is another second <code>j</code> in the range <code>[i + 1, x]</code> where <code>changeIndices[i]</code> can be marked.

The answer is the first value of <code>x</code> in the range <code>[1, m]</code> where it is possible to make <code>time_needed <= x</code>, or <code>-1</code> if there is no such second.