WHY

#include <iostream>
#include <vector>
#include <string>
#include <sstream>

using namespace std;

struct Node
{
    Node(string element, int order) {
        this->element = element;
        this->order = order;
    }

    Node() {
        this->element = '\0';
        this->order = -1;
    }

    string element;
    int order;
};
void insert(vector<Node>& nodes, string element, int order) {
    nodes.push_back(Node(element, order));
    int nodeIndex = nodes.size() - 1;
    int parent = (nodeIndex - 1) / 2;
    while (nodeIndex != 0 && nodes[nodeIndex].order < nodes[parent].order) {
        swap(nodes[nodeIndex], nodes[parent]);
        nodeIndex = parent;
        parent = (nodeIndex - 1) / 2;
    }
}
void heapify(vector<Node>& nodes, int index) {
    if (nodes.size() == index + 1) {
        return;
    }
    int smallest = index;
    if (index + 1 < nodes.size() && nodes[index + 1].order < nodes[index].order) {
        smallest = index + 1;
    }
    if (index + 2 < nodes.size() && nodes[index + 2].order < nodes[smallest].order) {
        smallest = index + 2;
    }
    if (smallest != index) {
        swap(nodes[index], nodes[smallest]);
        heapify(nodes, smallest);
    }
}

int main() {
    vector<Node> nodes = vector<Node>();
    string inputLine;
    getline(cin, inputLine);
    stringstream inputStream = stringstream(inputLine);
    string element = "";
    char buffer;
    while (inputStream >> noskipws >> buffer) {
        if (buffer == ' ') {
            int order;
            inputStream >> order;
            insert(nodes, element, order);
            element = "";
            inputStream >> noskipws >>buffer;
        }
        else {
            element += buffer;
        }
    }

    while (nodes.size() > 0) {
        cout << nodes[0].element;
        iter_swap(nodes.begin(), nodes.end() - 1);
        nodes.erase(nodes.end() - 1);
        heapify(nodes, 0);
    }
}