Leetcode 74、搜索二维矩阵

把矩阵看成一个有序的数组,二分查找

由题目得知，整个矩阵一行一行的看下来，是有序的，可以把整个矩阵看成一个有序的数组，来进行二分查找

class Solution {
    public boolean searchMatrix(int[][] matrix, int target) {
        int m = matrix.length;
        int n = matrix[0].length;
        int left = 0, right = m * n - 1;

        while(left <= right) {
            int mid = (right - left) / 2 + left;
            if(matrix[mid / n][mid % n] == target) {
                return true;
            }else if(matrix[mid / n][mid % n] < target) {
                left = mid + 1;
            }else {
                right = mid - 1;
            }
        }

        return false;
    }
}
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