2271 - Maximum White Tiles Covered by a Carpet.

Medium

You are given a 2D integer array tiles where <code>tilesi = l_i, r_i</code> represents that every tile j in the range <code>l_i<= j <= r_i</code> is colored white.

You are also given an integer carpetLen, the length of a single carpet that can be placed anywhere.

Return the maximum number of white tiles that can be covered by the carpet.

Example 1:

Input: tiles = \[\[1,5],10,11,12,18,20,25,30,32], carpetLen = 10

Output: 9

Explanation: Place the carpet starting on tile 10.

It covers 9 white tiles, so we return 9.

Note that there may be other places where the carpet covers 9 white tiles.

It can be shown that the carpet cannot cover more than 9 white tiles.

Example 2:

Input: tiles = \[\[10,11],1,1], carpetLen = 2

Output: 2

Explanation: Place the carpet starting on tile 10.

It covers 2 white tiles, so we return 2.

Constraints:

• <code>1 <= tiles.length <= 5 * 10⁴</code>

• tiles[i].length == 2

• <code>1 <= l_i<= r_i<= 10⁹</code>

• <code>1 <= carpetLen <= 10⁹</code>

• The tiles are non-overlapping.