L2-002 链表去重

#include <iostream>
#include <string.h>
#include <cstdio>
#include <algorithm>
#include <cstdlib>
#include <math.h>
#include <queue>
#include <vector>
#define maxn 100005
#define INF 0x3f3f3f3f
using namespace std;
typedef long long ll;
struct node
{
    int nextadr;
    int nkey;
}no[maxn];
int s,n,adr,key,nadr;
int del[maxn],vis[maxn],fir[maxn],sec[maxn];
int main()
{
    scanf("%d%d",&s,&n);
    for(int i=0;i<n;i++)
    {
        scanf("%d%d%d",&adr,&key,&nadr);
        no[adr].nextadr=nadr;
        no[adr].nkey=key;
    }
    int p=0,q=0;
    int ta=s;
    int tk=no[s].nkey;
    int tn=no[s].nextadr;
    if(tn==-1)
    {
        printf("%05d %d -1\n",ta,no[ta].nkey);
        return 0;
    }
    for(int i=0;i<n;i++)
    {
        if(!vis[abs(tk)])
        {
            vis[abs(tk)]=1;
            fir[p]=ta;
            sec[p]=no[ta].nextadr;
            p++;
        }
        else
        {
            del[q++]=ta;
            sec[p-1]=tn;
        }
        if(tn==-1)
        {
            sec[p-1]=-1;
            break;
        }
        ta=no[ta].nextadr;
        tk=no[ta].nkey;
        tn=no[ta].nextadr;
    }
    for(int i=0;i<p;i++)
    {
        if(sec[i]==-1)
            printf("%05d %d -1\n",fir[i],no[fir[i]].nkey);
        else
            printf("%05d %d %05d\n",fir[i],no[fir[i]].nkey,sec[i]);
    }
    for(int i=0;i<q-1;i++)
    {
        printf("%05d %d %05d\n",del[i],no[del[i]].nkey,del[i+1]);
    }
    printf("%05d %d -1\n",del[q-1],no[del[q-1]].nkey);
    return 0;
}