You are given an array of positive integers arr
. Perform some operations (possibly none) on arr
so that it satisfies these conditions:
- The value of the first element in
arr
must be1
. - The absolute difference between any 2 adjacent elements must be less than or equal to
1
. In other words,abs(arr[i] - arr[i - 1]) <= 1
for eachi
where1 <= i < arr.length
(0-indexed).abs(x)
is the absolute value ofx
.
There are 2 types of operations that you can perform any number of times:
- Decrease the value of any element of
arr
to a smaller positive integer. - Rearrange the elements of
arr
to be in any order.
Return the maximum possible value of an element in arr
after performing the operations to satisfy the conditions.
Example 1:
Input: arr = [2,2,1,2,1]
Output: 2
Explanation:
We can satisfy the conditions by rearranging arr so it becomes [1,2,2,2,1].
The largest element in arr is 2.
Example 2:
Input: arr = [100,1,1000]
Output: 3
Explanation:
One possible way to satisfy the conditions is by doing the following:
1. Rearrange arr so it becomes [1,100,1000].
2. Decrease the value of the second element to 2.
3. Decrease the value of the third element to 3.
Now arr = [1,2,3], which satisfies the conditions.
The largest element in arr is 3.
Example 3:
Input: arr = [1,2,3,4,5]
Output: 5
Explanation: The array already satisfies the conditions, and the largest element is 5.
Constraints:
- 1 <= arr.length <= 105
- 1 <= arr[i] <= 109