题目：https://pintia.cn/problem-sets/994805260223102976/problems/994805296180871168

这道题不是很难，写了一会，主要是没理解清楚题意，机试的时候一定要多多注意！！
重点是42-44行反转那里，其他都是题意没理解懂，模版题

代码

  1. #include<vector>
  2. #include<algorithm>
  3. #include<iostream>
  4. #include<cstdio>
  5. #include<math.h>
  6. using namespace std;
  8. const int maxn = 100010;
  9. struct Node{
  10.     int address, data, next;
  11.     bool flag;
  12.     int order;
  13. }node[maxn];
  15. bool cmp(Node a, Node b){
  16.     if(a.flag == false || b.flag == false) return a.flag > b.flag;
  17.     return a.order < b.order;
  18. }
  20. int main(){
  21.     for(int i = 0; i < maxn; i++){
  22.         node[i].flag = false;
  23.         node[i].order = maxn;
  24.     }
  25.     int begin, n, k;
  26.     scanf("%d%d%d", &begin, &n, &k);
  27.     int address, data, next;
  28.     for(int i = 0; i < n; i++){
  29.         scanf("%d%d%d", &address, &data, &next);
  30.         node[address].address = address;
  31.         node[address].data = data;
  32.         node[address].next = next;
  33.     }
  34.     int p = begin, count = 0;
  35.     while(p != -1){
  36.         node[p].order = count;
  37.         node[p].flag = true;
  38.         p = node[p].next;
  39.         count++;
  40.     }
  41.     sort(node, node + maxn, cmp);
  42.     for(int i = 0; i < count / k ; i++){
  43.         //printf("i = %d\n",i);
  44.         reverse(node + i * k, node + (i + 1) * k);
  45.     }
  46.     //if(count % 4 == 0) reverse(node + count - 4, node + count);
  47.     for(int i = 0; i < count; i++){
  48.         if(i != count - 1) printf("%05d %d %05d\n", node[i].address, node[i].data, node[i + 1].address);
  49.         else printf("%05d %d -1\n", node[i].address, node[i].data);
  50.     }
  51.     return 0;
  52. }