From 9cf4ad1ced6a72618aadc8262c7782b55bc9ba8c Mon Sep 17 00:00:00 2001 From: xiongraorao Date: Sun, 5 Aug 2018 21:05:37 +0800 Subject: [PATCH] =?UTF-8?q?=E6=8B=BC=E5=A4=9A=E5=A4=9A=E7=AC=94=E8=AF=95?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../java/com/raorao/interview/pdd/Carts.java | 16 ++++ .../com/raorao/interview/pdd/Friends.java | 75 ++++++++++++++++ .../raorao/interview/pdd/ListComplete.java | 90 +++++++++++++++++++ .../com/raorao/interview/pdd/MaxMultiply.java | 35 ++++++++ .../com/raorao/interview/pdd/Numbers.java | 58 ++++++++++++ .../java/com/raorao/interview/pdd/Square.java | 72 +++++++++++++++ interview/README.md | 6 ++ 7 files changed, 352 insertions(+) create mode 100644 code/src/main/java/com/raorao/interview/pdd/Carts.java create mode 100644 code/src/main/java/com/raorao/interview/pdd/Friends.java create mode 100644 code/src/main/java/com/raorao/interview/pdd/ListComplete.java create mode 100644 code/src/main/java/com/raorao/interview/pdd/MaxMultiply.java create mode 100644 code/src/main/java/com/raorao/interview/pdd/Numbers.java create mode 100644 code/src/main/java/com/raorao/interview/pdd/Square.java diff --git a/code/src/main/java/com/raorao/interview/pdd/Carts.java b/code/src/main/java/com/raorao/interview/pdd/Carts.java new file mode 100644 index 00000000..e67174bc --- /dev/null +++ b/code/src/main/java/com/raorao/interview/pdd/Carts.java @@ -0,0 +1,16 @@ +package com.raorao.interview.pdd; + +/** + * 去卡片. + * + * 题目描述： + * + * @author Xiong Raorao + * @since 2018-08-05-20:40 + */ +public class Carts { + + public static void main(String[] args) { + + } +} diff --git a/code/src/main/java/com/raorao/interview/pdd/Friends.java b/code/src/main/java/com/raorao/interview/pdd/Friends.java new file mode 100644 index 00000000..ee8caf06 --- /dev/null +++ b/code/src/main/java/com/raorao/interview/pdd/Friends.java @@ -0,0 +1,75 @@ +package com.raorao.interview.pdd; + +import java.util.ArrayList; +import java.util.Scanner; + +/** + * . + * + * @author Xiong Raorao + * @since 2018-08-05-20:03 + */ +public class Friends { + + public static void main(String[] args) { + Scanner scanner = new Scanner(System.in); + while (scanner.hasNextLine()) { + String[] input = scanner.nextLine().split(" "); + int userNum = Integer.parseInt(input[0]); + int targetUser = Integer.parseInt(input[1]); + int[][] relation = new int[userNum][userNum]; + for (int i = 0; i < userNum && scanner.hasNextLine(); i++) { + String ss = scanner.nextLine(); + String[] users = ss.split(" "); + for (String s : users) { + int user = Integer.parseInt(s); + relation[i][user] = 1; + relation[i][i] = 1; + } + //System.out.println(" line " + i ); + } + //System.out.println(" out: "); + System.out.println(process(relation, targetUser, userNum)); + } + + } + + private static int process(int[][] relation, int targetUser, int userNum) { + // 判断最可能的好友 + ArrayList stranger = new ArrayList<>(); + for (int i = 0; i < userNum; i++) { + if (relation[targetUser][i] != 1) { + stranger.add(i); + } + } + + if (userNum == 1) { + return -1; + } + + // 判断哪个陌生人和自己的共同好友多 + if (stranger.size() == 1) { + return stranger.get(0); + } + int resultUser = 0; + int maxFriends = getSameFriend(relation, stranger.get(0), targetUser, userNum); + for (int i = 1; i < stranger.size(); i++) { + int temp = getSameFriend(relation, stranger.get(i), targetUser, userNum); + if (temp > maxFriends) { + maxFriends = temp; + resultUser = stranger.get(i); + } + } + return resultUser; + } + + private static int getSameFriend(int[][] relation, int user1, int user2, int userNum) { + int count = 0; + for (int i = 0; i < userNum; i++) { + if (relation[user1][i] == 1 && relation[user2][i] == 1) { + count++; + } + } + return count; + } +} diff --git a/code/src/main/java/com/raorao/interview/pdd/ListComplete.java b/code/src/main/java/com/raorao/interview/pdd/ListComplete.java new file mode 100644 index 00000000..4e16716a --- /dev/null +++ b/code/src/main/java/com/raorao/interview/pdd/ListComplete.java @@ -0,0 +1,90 @@ +package com.raorao.interview.pdd; + +import java.util.Scanner; + +/** + * 列表补全问题. + * + * 描述： 在商城的某个位置有一个商品列表，该列表是由L1、L2两个子列表拼接而成。当用户浏览并翻页时，需要从列表L1、L2中获取商品进行展示。展示规则如下： + * + * 1. 用户可以进行多次翻页，用offset表示用户在之前页面已经浏览的商品数量，比如offset为4，表示用户已经看了4个商品 + * + * 2. n表示当前页面需要展示的商品数量 + * + * 3. 展示商品时首先使用列表L1，如果列表L1长度不够，再从列表L2中选取商品 + * + * 4. 从列表L2中补全商品时，也可能存在数量不足的情况 + * + * 请根据上述规则，计算列表L1和L2中哪些商品在当前页面被展示了 + * + * 输入描述： + * + * 每个测试输入包含1个测试用例，包含四个整数，分别表示偏移量offset、元素数量n，列表L1的长度l1，列表L2的长度l2。 + * + * 输出描述： + * + * 一行内输出四个整数分别表示L1和L2的区间start1，end1，start2，end2，每个数字之间有一个空格。 注意，区间段使用半开半闭区间表示，即包含起点，不包含终点。如果某个列表的区间为空，使用[0, + * 0)表示，如果某个列表被跳过，使用[len, len)表示，len表示列表的长度。 + * + * @author Xiong Raorao + * @since 2018-08-05-16:02 + */ +public class ListComplete { + + public static String process(String list) { + String[] arr = list.split(" "); + int offset = Integer.parseInt(arr[0]); + int n = Integer.parseInt(arr[1]); + int L1 = Integer.parseInt(arr[2]); + int L2 = Integer.parseInt(arr[3]); + + int[] out = new int[4]; + + if (offset + n < L1) { + out[0] = offset; + out[1] = offset + n; + out[2] = 0; + out[3] = 0; + } else if (offset < L1 && offset + n >= L1) { + out[0] = offset; + out[1] = L1; + out[2] = 0; + if (offset + n < L1 + L2) { + out[3] = offset + n - L1; + } else { + out[3] = L2; + } + } else if (offset >= L1 && offset <= L1 + L2) { + out[0] = L1; + out[1] = L1; + out[2] = offset - L1; + if (offset + n < L1 + L2) { + out[3] = offset + n - L1; + } else { + out[3] = L2; + } + } else if (offset > L1 + L2){ + out[0] = L1; + out[1] = L1; + out[2] = L2; + out[3] = L2; + } + + StringBuilder sb = new StringBuilder(); + sb.append(out[0]).append(" ") + .append(out[1]).append(" ") + .append(out[2]).append(" ") + .append(out[3]); + return sb.toString(); + + } + + + public static void main(String[] args) { + Scanner scanner = new Scanner(System.in); + while (scanner.hasNextLine()) { + String line = scanner.nextLine(); + System.out.println(process(line)); + } + } +} diff --git a/code/src/main/java/com/raorao/interview/pdd/MaxMultiply.java b/code/src/main/java/com/raorao/interview/pdd/MaxMultiply.java new file mode 100644 index 00000000..4993d2c6 --- /dev/null +++ b/code/src/main/java/com/raorao/interview/pdd/MaxMultiply.java @@ -0,0 +1,35 @@ +package com.raorao.interview.pdd; + +import java.util.Scanner; + +/** + * 最大乘积. + * + * @author Xiong Raorao + * @since 2018-08-05-17:03 + */ +public class MaxMultiply { + + private static int[] arr; + private static int size; + + public static void main(String[] args) { + for (int i = 0; i < size; i++) { + + } + } + + public static void read() { + Scanner scanner = new Scanner(System.in); + if (scanner.hasNextInt()) { + size = scanner.nextInt(); + arr = new int[size]; + } + if (scanner.hasNextLine()) { + String[] ss = scanner.nextLine().split(" "); + for (int i = 0; i < ss.length; i++) { + arr[i] = Integer.parseInt(ss[i]); + } + } + } +} diff --git a/code/src/main/java/com/raorao/interview/pdd/Numbers.java b/code/src/main/java/com/raorao/interview/pdd/Numbers.java new file mode 100644 index 00000000..eefb69cf --- /dev/null +++ b/code/src/main/java/com/raorao/interview/pdd/Numbers.java @@ -0,0 +1,58 @@ +package com.raorao.interview.pdd; + +import java.util.Scanner; + +/** + * 有趣的变换. + * + * @author Xiong Raorao + * @since 2018-08-05-19:52 + */ +public class Numbers { + + public static int intSum(String string) { + if (string.equals("0")) { + return 1; + } + if (string.startsWith("0")) { + return 0; + } else { + return 1; + } + } + + public static int foatSum(String string) { + if (string.endsWith("0")) { + return 0; + } + if (string.startsWith("0")) { + return 1; + } else { + return string.length() - 1; + } + + + } + + public static int process(String string) { + int count = 0; + for (int i = 1; i < string.length(); i++) { + count += + intSum(string.substring(0, i)) * foatSum(string.substring(i, string.length())) + + intSum(string.substring(0, i)) * intSum(string.substring(i, string.length())) + + + foatSum(string.substring(0, i)) * intSum( + string.substring(i, string.length())) + + foatSum(string.substring(0, i)) * foatSum( + string.substring(i, string.length())); + } + return count; + } + + public static void main(String[] args) { + Scanner scanner = new Scanner(System.in); + String input = scanner.nextLine(); + System.out.println(process(input)); + } + +} \ No newline at end of file diff --git a/code/src/main/java/com/raorao/interview/pdd/Square.java b/code/src/main/java/com/raorao/interview/pdd/Square.java new file mode 100644 index 00000000..aae158c8 --- /dev/null +++ b/code/src/main/java/com/raorao/interview/pdd/Square.java @@ -0,0 +1,72 @@ +package com.raorao.interview.pdd; + +import java.util.Scanner; + +/** + * 旋转的字符串. + * + * 题目要求： 求给定的数字的字符串 + * + * @author Xiong Raorao + * @since 2018-08-05-19:04 + */ +public class Square { + + private static void process(String ss) { + char[] arr = ss.toCharArray(); + int a; + char[][] result; + if (ss.length() == 0) { + System.out.println(); + } + if (ss.length() % 4 == 0) { + a = ss.length() / 4 + 1; + result = new char[a][a]; + + // 第一行 + for (int i = 0; i < a; i++) { + result[0][i] = arr[i]; + } + + // 最后一行 + for (int i = 0; i < a; i++) { + result[a - 1][a - i - 1] = arr[2 * a - 2 + i]; + } + + // 右边 + for (int i = 0; i < a - 2; i++) { + result[i + 1][a - 1] = arr[a + i]; + } + + // 左边 + for (int i = 0; i < a - 2; i++) { + result[a - 2 - i][0] = arr[3 * a - 2 + i]; + } + + // 打印 + print(result); + } + } + + public static void main(String[] args) { + Scanner scanner = new Scanner(System.in); + while (scanner.hasNextLine()) { + process(scanner.nextLine()); + } + } + + private static void print(char[][] arr) { + int a = arr.length; + for (int i = 0; i < a; i++) { + for (int j = 0; j < a; j++) { + if (i == 0 || j == 0 || i == a - 1 || j == a - 1) { + System.out.print(arr[i][j] + ""); + } else { + System.out.print(" "); + } + } + System.out.println(); + } + } + +} diff --git a/interview/README.md b/interview/README.md index 4324a310..2ee79475 100644 --- a/interview/README.md +++ b/interview/README.md @@ -66,6 +66,12 @@ df, disk free, 通过文件系统来快速获取空间大小的信息，当我 (6) TCP 四次挥手的过程？time_out的缺点？ (7) mysql 的 group by 和 partition by? 答：group by 用来做聚合操作，partition by 用于对某个字段分区，然后做某些操作。 + +普通的聚合函数用group by分组，每个分组返回一个统计值，而分析函数采用partition by分组，并且每组每行都可以返回一个统计值。 +分析函数的形式：分析函数带有一个开窗函数over()，包含三个分析子句:分组(partition by), 排序(order by), 窗口(rows) 。 + +parition by 针对Oracle数据库 + [参考链接](https://blog.csdn.net/cyl937/article/details/19930349) (8) 海量数据去重，例如大量的IP地址，如何去重？ 答：MapReduce