Search a 2D Matrix - LeetCode

题意

Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:

• Integers in each row are sorted from left to right.
• The first integer of each row is greater than the last integer of the previous row.

Example 1:

Input: matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,50]], target = 3
Output: true

Example 2:

Input: matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,50]], target = 13
Output: false

Example 3:

Input: matrix = [], target = 0
Output: false

Constraints:

• m == matrix.length
• n == matrix[i].length
• 0 <= m, n <= 100
• 104 <= matrix[i][j], target <= 104

题解1：一维化+二分