1948B.cpp

#include <bits/stdc++.h>
using namespace std;

struct Node
{
    int data;
    Node *next;
    Node(int data)
    {
        this->data = data;
        this->next = nullptr;
    }
};

int getdigit(int num)
{
    int digit = 0;
    while (num != 0)
    {
        num /= 10;
        digit++;
    }
    return digit;
}


int main()
{
    int t;
    cin >> t;
    while (t--)
    {
        int n;
        cin >> n;

        Node *head = nullptr, *tail = nullptr;
        for (int i = 0; i < n; i++)
        {
            int val;
            cin >> val;
            Node *newnode = new Node(val);
            if (!head)
                head = tail = newnode;
            else
            {
                tail->next = newnode;
                tail = newnode;
            }
        }

        Node *prev = nullptr;
        Node *temp = head;
        bool yes = true;

        while (temp && temp->next)
        {
            int p_f = temp->data;
            int p_s = temp->next->data;

            int d_f = getdigit(p_f);
            if ((p_f > p_s) && (d_f == 1))
            {
                cout << "NO\n";
                yes = false;
                break;
            }
            else if (p_f > p_s)
            {
                vector<int> digit_arr;
                int num = p_f;
                while (num)
                {
                    digit_arr.push_back(num % 10);
                    num /= 10;
                }
                if (digit_arr.empty())
                    digit_arr.push_back(0); 
                reverse(digit_arr.begin(), digit_arr.end());

                Node *new_head = nullptr, *new_tail = nullptr;
                for (int d : digit_arr)
                {
                    Node *node = new Node(d);
                    if (!new_head)
                        new_head = new_tail = node;
                    else
                    {
                        new_tail->next = node;
                        new_tail = node;
                    }
                }

                if (prev)
                    prev->next = new_head;
                else
                    head = new_head;

                new_tail->next = temp->next;
                temp = head;             
                prev = nullptr;             
            }
            else
            {
                prev = temp;
                temp = temp->next;
            }
        }

        if (yes)
        {
            cout << "YES\n";
        }
    }

    return 0;
}