240. 搜索二维矩阵 II -- 力扣 --JAVA

题目

解题思路一

1. 逐个遍历

代码展示

class Solution {
    public boolean searchMatrix(int[][] matrix, int target) {
        int m = matrix.length;
        int n = matrix[0].length;
        for (int i = 0; i < m; i++){
            for (int j = 0; j < n; j++){
                if(matrix[i][j] == target){
                    return true;
                }
            }
        }
        return false;
    }
}

 解题思路

1. 对每一行数据进行二分法查找

代码展示

class Solution {
    public boolean searchMatrix(int[][] matrix, int target) {
        int m = matrix.length;
        int n = matrix[0].length;
        for (int i = 0; i < m; i++){
            int left = 0, right = n - 1;
            while (left <= right){
                int mid = (left + right) / 2;
                if(matrix[i][mid] == target){
                    return true;
                }
                if(matrix[i][mid] > target){
                    right = mid - 1;
                } else {
                    left = mid + 1;
                }
            }
        }
        return false;
    }
}