自己测试可以,但是PTA只能运行只能得4分,哪位大神帮我看看错哪了。
笔记和代码的思路来源:
好大学慕课浙江大学陈越、何钦铭的《数据结构》
1 package ygh.study.demo1; 2 3 import java.util.ArrayList; 4 import java.util.List; 5 import java.util.Scanner; 6 /* 7 Given a constant KKK and a singly linked list LLL, you are supposed to reverse the links of every KKK elements on LLL. For example, given LLL being 1→2→3→4→5→6, if K=3K = 3K=3, then you must output 3→2→1→6→5→4; if K=4K = 4K=4, you must output 4→3→2→1→5→6. 8 Input Specification: 9 10 Each input file contains one test case. For each case, the first line contains the address of the first node, a positive NNN (≤105le 10^5≤105) which is the total number of nodes, and a positive KKK (≤Nle N≤N) which is the length of the sublist to be reversed. The address of a node is a 5-digit nonnegative integer, and NULL is represented by -1. 11 12 Then NNN lines follow, each describes a node in the format: 13 14 Address Data Next 15 16 where Address is the position of the node, Data is an integer, and Next is the position of the next node. 17 Output Specification: 18 19 For each case, output the resulting ordered linked list. Each node occupies a line, and is printed in the same format as in the input. 20 Sample Input: 21 22 00100 6 4 23 00000 4 99999 24 00100 1 12309 25 68237 6 -1 26 33218 3 00000 27 99999 5 68237 28 12309 2 33218 29 30 Sample Output: 31 32 00000 4 33218 33 33218 3 12309 34 12309 2 00100 35 00100 1 99999 36 99999 5 68237 37 68237 6 -1 38 */ 39 public class Demo1 { 40 41 public static void main(String[] args) { 42 List<Node> nodeList = new ArrayList<Node>(); 43 // nodeList.add(new Node("00000", 4, "99999")); 44 // nodeList.add(new Node("00100", 1, "12309")); 45 // nodeList.add(new Node("68237", 6, "-1")); 46 // nodeList.add(new Node("33218", 3, "00000")); 47 // nodeList.add(new Node("12309", 2, "33218")); 48 // nodeList.add(new Node("99999", 5, "68237")); 49 Scanner sc = new Scanner(System.in); 50 String initAddress = sc.next(); 51 int n = sc.nextInt(); 52 int k = sc.nextInt(); 53 for (int i = 0; i < n; i++) { 54 String address = sc.next(); 55 int element = sc.nextInt(); 56 String nextAddrss = sc.next(); 57 Node node = new Node(address, element, nextAddrss); 58 nodeList.add(node); 59 } 60 sc.close(); 61 List<Node> sortedList = sort(nodeList, initAddress, n); 62 transmit(sortedList, k); 63 for (Node node : sortedList) { 64 System.out.println(node.toString()); 65 System.err.println(); 66 } 67 68 } 69 70 public static void transmit(List<Node> list, int k) { 71 int length = list.size(); 72 int i = 0; 73 if (length < k) { 74 track(list, 0, length); 75 return; 76 } else { 77 while (i <= length) { 78 if (i + k <= length) { 79 track(list, i, i + k); 80 i = i + k; 81 } else { 82 track(list, i + k, length); 83 i = i + k; 84 } 85 } 86 } 87 } 88 89 public static void track(List<Node> list, int begin, int end) { 90 int mid = (begin + end) / 2; 91 for (int i = begin; i < mid; i++) { 92 Node temp = list.get(i); 93 list.set(i, list.get(end - i - 1)); 94 list.set(end - i - 1, temp); 95 } 96 } 97 98 public static List<Node> sort(List<Node> list, String initAddress, int length) { 99 List<Node> tempList = new ArrayList<Node>(); 100 tempList.add(getNodeByAddress(list, initAddress)); 101 for (int i = 1; i < length; i++) { 102 tempList.add(getNodeByAddress(list, tempList.get(i - 1).getNextAddress())); 103 } 104 105 return tempList; 106 } 107 108 public static Node getNodeByAddress(List<Node> list, String address) { 109 for (Node node : list) { 110 if (node.getAddress().equals(address)) { 111 return node; 112 } 113 } 114 return null; 115 } 116 117 } 118 119 class Node { 120 private String address; 121 122 private int element; 123 124 private String nextAddress; 125 126 public String getAddress() { 127 return address; 128 } 129 130 public void setAddress(String address) { 131 this.address = address; 132 } 133 134 public int getElement() { 135 return element; 136 } 137 138 public void setElement(int element) { 139 this.element = element; 140 } 141 142 public String getNextAddress() { 143 return nextAddress; 144 } 145 146 public void setNextAddress(String nextAddress) { 147 this.nextAddress = nextAddress; 148 } 149 150 public Node(String address, int element, String nextAddress) { 151 super(); 152 this.address = address; 153 this.element = element; 154 this.nextAddress = nextAddress; 155 } 156 157 public Node() { 158 super(); 159 } 160 161 @Override 162 public String toString() { 163 return this.getAddress() + " " + this.getElement() + " " + this.getNextAddress(); 164 } 165 166 }