LeetCode-in-All

74. Search a 2D Matrix

Medium

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.

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 <= 104

Solution

func searchMatrix(matrix [][]int, target int) bool {
	endRow := len(matrix)
	endCol := len(matrix[0])
	targetRow := 0
	result := false
	for i := 0; i < endRow; i++ {
		if matrix[i][endCol-1] >= target {
			targetRow = i
			break
		}
	}
	for i := 0; i < endCol; i++ {
		if matrix[targetRow][i] == target {
			result = true
			break
		}
	}
	return result
}

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