#Leetcode# 240. Search a 2D Matrix II

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

 

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.

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.

代码：

class Solution {
public:
    bool searchMatrix(vector<vector<int>>& matrix, int target) {
        if(matrix.empty() || matrix[0].empty()) return false;
        int n = matrix.size(), m = matrix[0].size();
        int row = 0, line = m - 1;
        while(1) {
            if(matrix[row][line] == target) return true;
            else if(matrix[row][line] > target) line --;
            else row ++;
 
            if(row >= n || line < 0) break;
        }
        return false;
    }
};

　　

LeetCode 的第一百题！！！

今天不想写了鸭 明天去绍兴啦啦啦 肥去收拾东西准备一下啦 期待下一个 100 题