Given an array arr[] of measurement N, the duty is to search out the utmost worth that may be obtained by following the under circumstances:

• Choose any component (say ok) from the array and improve all different parts by 1.
• Within the subsequent step, soar solely to the index with a price ok+1.
• In the long run, you’re on the most worth.

Examples:

Enter: N = 4, arr[] ={1, 2, 1, 3}
Output: 3
Clarification: If began from index 0 with a top of 1 unit, then,  
the brand new worth of array will probably be [1, 3, 2, 4]. 
Then soar to the index with (1+1 = 2) ie 2nd index,  
The up to date values are [2, 4, 2, 5]. Can’t be on the most worth at finish
The primary chosen worth was 3 at index 3. 
The up to date values are [2, 3, 2, 3]. Max achieved -3. Therefore ans = 3;

Enter: N = 4, arr[]={1, 2, 3, 3}
Output: 4

Strategy: The issue will be solved based mostly on the next remark:

On remark, we will understand that for reaching most top we’ve two choices

• Instantly choosing the utmost heighted podium initially accessible.
• Selecting all the weather (say complete y) with similar worth (say x). So highest quantity that may be reached is (x + y – 1).

Comply with the under steps to resolve the issue:

• Kind the array in rising order.
• Search for the span of the identical worth parts and get the utmost worth that may be achieved from that span utilizing the above thought.
• Carry out this for all accessible spans and retailer the utmost.
• Return the most because the required reply.

Beneath is the implementation of the above strategy.

Time Complexity: O(N*logN)
Auxiliary House: O(1)