Pat 1097 duplication on a linked list (25 points)

#include <iostream>
#include <vector>
#include <set>
using namespace std;
struct node{
    
   int address,val;
};
int Data[100005],Next[100005];
int main() {
       
    int first,n,temp;
    cin>>first>>n;
    vector<node>a(n),a1,a2;
    for(int i=0;i<n;i++){
    
        scanf("%d",&temp);
        scanf("%d %d",&Data[temp],&Next[temp]);
    }
    int i=0;
    while(first!=-1){
    
        a[i++]={
    first,Data[first]};
        first=Next[first];
    }
    set<int>s;
    for(int i=0;i<n;i++){
    
        if(s.find(abs(a[i].val))==s.end()){
    
            s.insert(abs(a[i].val));
            a1.push_back({
    a[i].address,a[i].val});
        }else{
    
            a2.push_back({
    a[i].address,a[i].val});
        }
    }
    for(int i=0;i<a1.size();i++){
    
        printf("%05d %d ",a1[i].address,a1[i].val);
        if(i!=a1.size()-1) printf("%05d\n",a1[i+1].address);
        else cout<<-1<<endl;
    }
    for(int i=0;i<a2.size();i++){
    
        printf("%05d %d ",a2[i].address,a2[i].val);
        if(i!=a2.size()-1) printf("%05d\n",a2[i+1].address);
        else cout<<-1<<endl;
    }
    system("pause");
    return 0;
}

#include <cstdio>
#include <stdlib.h>
#include <algorithm>
using namespace std;
const int maxn = 100000;
struct NODE {
    
    int address, key, next, num = 2 * maxn;
}node[maxn];
bool exist[maxn];
int cmp1(NODE a, NODE b){
    
    return a.num < b.num;
}
int main() {
    
    int begin, n, cnt1 = 0, cnt2 = 0, a;
    scanf("%d%d", &begin, &n);
    for(int i = 0; i < n; i++) {
    
        scanf("%d", &a);
        scanf("%d%d", &node[a].key, &node[a].next);
        node[a].address = a;
    }
    for(int i = begin; i != -1; i = node[i].next) {
    
        if(exist[abs(node[i].key)] == false) {
    
            exist[abs(node[i].key)] = true;
            node[i].num = cnt1;
            cnt1++;
        }
        else {
    
            node[i].num = maxn + cnt2;
            cnt2++;
        }
    }
    sort(node, node + maxn, cmp1);
    int cnt = cnt1 + cnt2;
    for(int i = 0; i < cnt; i++) {
    
        if(i != cnt1 - 1 && i != cnt - 1) {
    
            printf("%05d %d %05d\n", node[i].address, node[i].key, node[i+1].address);
        } else {
    
            printf("%05d %d -1\n", node[i].address, node[i].key);
        }
    }
    return 0;
}