标签:des style os io strong 数据 for ar
Given a constant K and a singly linked list L, you are supposed to reverse the links of every K elements on L. For example, given L being 1→2→3→4→5→6, if K = 3, then you must output 3→2→1→6→5→4; if K = 4, you must output 4→3→2→1→5→6.
Input Specification:
Each input file contains one test case. For each case, the first line contains the address of the first node, a positive N (<= 105) which is the total number of nodes, and a positive K (<=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.
Then N lines follow, each describes a node in the format:
Address Data Next
where Address is the position of the node, Data is an integer, andNext is the position of the next node.
Output Specification:
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.
Sample Input:00100 6 4 00000 4 99999 00100 1 12309 68237 6 -1 33218 3 00000 99999 5 68237 12309 2 33218Sample Output:
00000 4 33218 33218 3 12309 12309 2 00100 00100 1 99999 99999 5 68237 68237 6 -1
反转链表,但是此链表非彼链表。题目意思是说链表的节点由两个地址一个数值组成,给定一个数k,那么链表里面以k个节点为一组进行反转,但是要保证各节点之间的地址相连无误。
刚开始的思路是:用字符串来存储地址,因为地址一定是5位数,结果最后倒数第二个点会超时。看来读入一个类真的很费时间,后来改成了char[ ]虽然超时没了,但是判断起来还是很不方便。后来看了别人的代码发现这么个东西:printf("%05d",n);用5位长度输出一个数字,少的部分用0来填充。这样就可以用int来存地址,映射完全可以用数组来替代。
除了上述数据结构的简化,这个题目还有几点要注意:
【1】输入的点可能有无用的点,这些点要忽略。
【2】输出-1的时候前面没有0
【3】反转的时候节点本身的地址是不变的,但是下一个地址要变,这里我用了输出两次本次地址来替代。
【4】注意反转两轮及以上的情况。
Ac代码:
// pat-1074-ans.cpp : 定义控制台应用程序的入口点。 // #include "stdafx.h" #include"iostream" #include"stdio.h" #include "deque" using namespace std; class node{ public: int addr; int val; int next; node(int a,int v,int n):addr(a),val(v),next(n){} node(){} }; node an[100000]; deque<node> ans; int time=0; void output(deque<node>& ans) { if (time>0&&!ans.empty()) { printf("%05d\n",ans.back().addr); time--; } int index=ans.size()-2; int temp=ans.back().next; while (!ans.empty()) { if (index==-1)//最后一个 { printf("%05d",ans.back().addr); printf(" %d ",ans.back().val); time++; } else { printf("%05d",ans.back().addr); printf(" %d ",ans.back().val); if (ans.at(index).addr==-1) { printf("%d\n",ans.at(index).addr); }else printf("%05d\n",ans.at(index).addr); } ans.pop_back(); index-=1; } } void output_front(deque<node>& ans) { if (time>0&&!ans.empty()) { printf("%05d\n",ans.front().addr); time--; } while (!ans.empty()) { printf("%05d",ans.front().addr); printf(" %d ",ans.front().val); if (ans.back().next==-1) { printf("%d\n",ans.front().next); }else printf("%05d\n",ans.front().next); ans.pop_front(); } } int main() { int n=0,k=0,head=0; cin>>head>>n>>k; int addr=0,val=0,next=0; for (int i=0;i<n;i++) { cin>>addr>>val>>next; an[addr].addr=addr; an[addr].val=val; an[addr].next=next; } int cnt=0; int index=head; bool apend=false; while(cnt<n) { next=an[index].next; node tempn; tempn.addr=an[index].addr; tempn.val=an[index].val; tempn.next=next; ans.push_back(tempn); cnt++; if (cnt%k==0) { output(ans); } if (next==-1) { if (ans.empty()) { apend=true; } output_front(ans); if (apend) { printf("-1\n"); } break; } index=next; } return 0; }
标签:des style os io strong 数据 for ar
原文地址:http://blog.csdn.net/linsheng9731/article/details/38496847