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
.
class Solution { public: bool searchMatrix(vector<vector<int> > &matrix, int target) { if (matrix.empty() || matrix[0].empty()) return false; if (target < matrix[0][0] || target > matrix.back().back()) return false; int x = matrix.size() - 1, y = 0; while (true) { if (matrix[x][y] > target) --x; else if (matrix[x][y] < target) ++y; else return true; if (x < 0 || y >= matrix[0].size()) break; } return false; } };
原文地址:https://www.cnblogs.com/Mered1th/p/10591292.html
时间: 2024-10-17 10:12:57