Problem Description

Write an efficient algorithm that searches for a value target in an m x n integer matrix 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.

Examples

Example 1:

Input: matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 3
Output: true

Example 2:

Input: matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 13
Output: false

Constraints:

• m == matrix.length
• n == matrix[i].length
• 1 <= m, n <= 100
• 104 <= matrix[i][j], target <= $10^4$

解析

題目給定一個 2 維的矩陣，然後這矩陣是一個排序過的矩陣

照著 row-base 方式排列，所以要找到有效率的方式去判斷值有沒有在矩陣