Ближайшее число

# Ближайшее число

#include <iostream>
#include <fstream>

struct Node {
    int value;
    Node* next;
};

void push(Node** head, int value) {
    Node* new_node = new Node[sizeof(Node)];
    new_node->next = *head;
    new_node->value = value;
    *head = new_node;

}

void pop(Node** head) {
    if ((*head) != nullptr)
        *head = (*head)->next;
}

int top(Node* head) {
    if (head != nullptr)
        return head->value;
}

int isEmpty(Node** head){
    if (*head == nullptr)
        return 1;
    return 0;
}

int main() {
    std::ifstream fin("input.txt");
    std::ofstream fout("output.txt");
    int N;
    fin >> N;
    int a[N];
    for (int i = 0; i < N; ++i){
        fin >> a[i];
    }

    Node *stack = nullptr;
    Node *index = nullptr;

    push(&stack, a[0]);
    push(&index, 0);

    for (int i = 1; i < N; ++i){
        while (!isEmpty(&stack) && top(stack) < a[i]){
            a[top(index)] = a[i];
            pop(&stack);
            pop(&index);
        }
        push(&stack, a[i]);
        push(&index, i);

    }
    for (int i = 0; i < N; ++i)
        fout << a[i] << " ";

    fin.close();
    fout.close();

    return 0;
}