Java实现 LeetCode 240 搜索二维矩阵 II

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