You are given a 2D array of integers envelopes where envelopes[i] = [wi, hi] represents the width and the height of an envelope.
One envelope can fit into another if and only if both the width and height of one envelope are greater than the other envelope's width and height.
Return the maximum number of envelopes you can Russian doll (i.e., put one inside the other).
Note: You cannot rotate an envelope.
Examples
Example 1
Input: envelopes = [[5,4],[6,4],[6,7],[2,3]]
Output: 3
Explanation: The maximum number of envelopes you can Russian doll is 3 ([2,3] => [5,4] => [6,7]).
Example 2
Input: envelopes = [[1,1],[1,1],[1,1]]
Output: 1
Constraints
1 <= envelopes.length <= 105
envelopes[i].length == 2
1 <= wi, hi <= 105
354. Russian Doll Envelopes
Hard
50 Points
Array
Binary Search
Dynamic Programming
Sorting
You are given a 2D array of integers envelopes where envelopes[i] = [wi, hi] represents the width and the height of an envelope.
One envelope can fit into another if and only if both the width and height of one envelope are greater than the other envelope's width and height.
Return the maximum number of envelopes you can Russian doll (i.e., put one inside the other).
Note: You cannot rotate an envelope.
Examples
Example 1
Input: envelopes = [[5,4],[6,4],[6,7],[2,3]]
Output: 3
Explanation: The maximum number of envelopes you can Russian doll is 3 ([2,3] => [5,4] => [6,7]).
Example 2
Input: envelopes = [[1,1],[1,1],[1,1]]
Output: 1
Constraints
1 <= envelopes.length <= 105
envelopes[i].length == 2
1 <= wi, hi <= 105
Russian Doll Envelopes - Practice Coding | SlaveCode