【Leetcode】Search a 2D Matrix II

题目链接：https://leetcode.com/problems/search-a-2d-matrix-ii/
题目：

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 in ascending from left to right.
• Integers in each column are sorted in ascending from top to bottom.

For example,

Consider the following matrix:

[
  [1,   4,  7, 11, 15],
  [2,   5,  8, 12, 19],
  [3,   6,  9, 16, 22],
  [10, 13, 14, 17, 24],
  [18, 21, 23, 26, 30]
]

Given target = 5, return true.

Given target = 20, return false.

public boolean searchMatrix(int[][] matrix, int target) {  
int j = matrix[0].length-1,i=0;   
while(i<matrix.length&&j>=0){  
     if(matrix[i][j]>target){  
         j--;  
     }else if(matrix[i][j]<target){  
         i++;  
     }else{  
         return true;  
     }  
 }  
return false;  
}  

【Leetcode】Search a 2D Matrix II

原文：http://blog.csdn.net/yeqiuzs/article/details/51501280