题目

解法1

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#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;

struct Node {
    int data;
    string next;
};

int main() {
    string head;
    int n, k;
    cin >> head >> n >> k;

    unordered_map<string, Node> map;
    vector<string> negative, between, greater; // 三个类别的地址列表

    // 读取链表数据
    for (int i = 0; i < n; i++) {
        string addr;
        Node node;
        cin >> addr >> node.data >> node.next;
        map[addr] = node; // 存入哈希表
    }

    // 遍历原链表，将节点分类
    string curr = head;
    while (curr != "-1") {
        int val = map[curr].data;
        if (val < 0) {
            negative.push_back(curr);
        } else if (val <= k) {
            between.push_back(curr);
        } else {
            greater.push_back(curr);
        }
        curr = map[curr].next; // 移动到下一个节点
    }

    // 重新组织链表顺序
    vector<string> result;
    result.insert(result.end(), negative.begin(), negative.end());
    result.insert(result.end(), between.begin(), between.end());
    result.insert(result.end(), greater.begin(), greater.end());

    // 输出新链表
    for (size_t i = 0; i < result.size(); i++) {
        string addr = result[i];
        string nextAddr = (i + 1 < result.size()) ? result[i + 1] : "-1";
        printf("%s %d %s\n", addr.c_str(), map[addr].data, nextAddr.c_str());
    }

    return 0;
}