Write an efficient algorithm that searches for a value in an m x n matrix. This matrix has the following properties:
For example,
Consider the following matrix:
[ [1, 3, 5, 7], [10, 11, 16, 20], [23, 30, 34, 50] ]
Given target = 3, return true.
1 public class Solution { 2 public boolean searchMatrix(int[][] matrix, int target) { 3 int line=0; 4 if (matrix.length<1) { 5 return false; 6 } 7 if (target<matrix[0][0]) { 8 return false; 9 } 10 for (int i = 1; i < matrix.length; i++) { 11 if (matrix[i][0]>target) { 12 line=i-1; 13 break; 14 } 15 if (matrix[i][0]==target) { 16 return true; 17 } 18 if (matrix[i][matrix[i].length-1]>=target) { 19 line=i; 20 } 21 } 22 23 for (int is : matrix[line]) { 24 if (is==target) { 25 return true; 26 } 27 } 28 return false; 29 } 30 }
原文：http://www.cnblogs.com/birdhack/p/4028391.html