CODE 59. Search a 2D Matrix

版权声明：本文为博主原创文章，转载请注明出处，谢谢!

版权声明：本文为博主原创文章，转载请注明出处：http://blog.jerkybible.com/2013/10/04/2013-10-04-CODE 59 Search a 2D Matrix/

访问原文「CODE 59. Search a 2D Matrix」

Write an efficient algorithm that searches for a value in anmxnmatrix. 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.

For example,
Consider the following matrix:
[
[1, 3, 5, 7],
[10, 11, 16, 20],
[23, 30, 34, 50]
]

Giventarget=3, returntrue.

public boolean searchMatrix(int[][] matrix, int target) {
	// Note: The Solution object is instantiated only once and is reused by
	// each test case.
	if (null == matrix || matrix.length <= 0) {
		return false;
	}
	int rows = matrix.length;
	int cols = matrix[0].length;
	int all = rows * cols;
	boolean finded = false;
	int i;
	for (i = 0; i < all - 1; i++) {
		if (matrix[i / cols][i % cols] > matrix[(i + 1) / cols][(i + 1)
				% cols]) {
			break;
		}
		if (matrix[i / cols][i % cols] == target) {
			finded = true;
		}
	}
	if (i < all - 1) {
		return false;
	} else if (matrix[rows - 1][cols - 1] == target) {
		finded = true;
	}
	return finded;
}