牛客--二维数组查找算法

在一个二维数组中（每个一维数组的长度相同），每一行都按照从左到右递增的顺序排序，每一列都按照从上到下递增的顺序排序。请完成一个函数，输入这样的一个二维数组和一个整数，判断数组中是否含有该整数。

/** * @author ：Dennis * @date ：Created in 4/3/2020 21:10 * @description： * @modified By： * @version: */ public class Solution { /** * Plan A * find column,then,find target by binary search * * @param target * @param array * @return */ public static boolean FindPlanA(int target, int[][] array) { if (array.length == 0) return false; for (int i = 0; i < array.length; i++) { if (array[i].length == 0) return false; if (array[i][0] > target || array[i][array[i].length - 1] < target) continue; //binary search int low, mid, high; low = 0; high = array[i].length - 1; while (low <= high) { mid = low + (high - low) / 2; if (array[i][mid] == target) return true; else if (array[i][mid] > target) { high = mid - 1; } else { low = mid + 1; } } } return false; }/** * Plan B * find from the bottom left corner, * if array[i][j]>target, go up * if array[i][j]= 0) { if (array[i][j] == target) return true; else if (array[i][j] > target) { j--; } else { i++; } } return false; }public static void main(String[] args) { int[][] array = new int[4][4]; array[0] = new int[]{0, 1, 2, 3}; array[1] = new int[]{4, 5, 6, 7}; array[2] = new int[]{8, 9, 10, 11}; array[3] = new int[]{12, 13, 14, 15}; boolean stat = FindPlanB(0, array); System.out.println("plan a:" + stat); stat = FindPlanB(0, array); System.out.println("plan b:" + stat); } }

【牛客--二维数组查找】题目地址：https://www.nowcoder.com/questionTerminal/abc3fe2ce8e146608e868a70efebf62e?orderByHotValue=https://www.it610.com/article/1&questionTypes=000100&page=1&onlyReference=false