using System;
using System.Text;
using System.Collections.Generic;
using static System.Math;
using System.Linq;
using static System.Array;

namespace DigitsParades
{

    class Programk
    {
        static void Main(string[] args)
        {
            //var NMK = Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToArray();
            var N = long.Parse(Console.ReadLine());
            var non = new int[100];
            var ans = 0;
            for (int i = 1; i <= N; i++)
            {
                
                var fig = i.ToString().Length;
                var head = i - (i / 10) * 10;
                var top = i / ((int)Pow(10, fig - 1));
               // Console.WriteLine(i+" "+top +" "+ head);

                if (top*head > 0)
                {
                  //ans += non[10 * top + head]+non[10 * head + top];
                    if(top == head)
                    {
                        ans += 2*non[10 * head + top];
                        non[10 * top + head]++;
                        ans++;
                    }
                    else
                    {
                        ans += 2*non[10 * top + head];
                       // non[10 * top + head]++;
                        non[10 * head + top]++;
                    }
                }
            }
            Console.WriteLine(ans);
        }
    }

    #region スキャナー
    class Scanner
    {
        public Scanner()
        {
            _pos = 0;
            _line = new string[0];
        }

        const char Separator = ' ';
        private int _pos;
        private string[] _line;

        #region スペース区切りで取得

        public string Next()
        {
            if (_pos >= _line.Length)
            {
                _line = Console.ReadLine().Split(Separator);
                _pos = 0;
            }

            return _line[_pos++];
        }

        public int NextInt()
        {
            return int.Parse(Next());
        }

        public long NextLong()
        {
            return long.Parse(Next());
        }

        public double NextDouble()
        {
            return double.Parse(Next());
        }

        #endregion

        #region 型変換

        private int[] ToIntArray(string[] array)
        {
            var result = new int[array.Length];
            for (int i = 0; i < array.Length; i++)
            {
                result[i] = int.Parse(array[i]);
            }

            return result;
        }

        private long[] ToLongArray(string[] array)
        {
            var result = new long[array.Length];
            for (int i = 0; i < array.Length; i++)
            {
                result[i] = long.Parse(array[i]);
            }

            return result;
        }

        private double[] ToDoubleArray(string[] array)
        {
            var result = new double[array.Length];
            for (int i = 0; i < array.Length; i++)
            {
                result[i] = double.Parse(array[i]);
            }

            return result;
        }

        #endregion

        #region 配列取得

        public string[] Array()
        {
            if (_pos >= _line.Length)
                _line = Console.ReadLine().Split(Separator);

            _pos = _line.Length;
            return _line;
        }

        public int[] IntArray()
        {
            return ToIntArray(Array());
        }

        public long[] LongArray()
        {
            return ToLongArray(Array());
        }

        public double[] DoubleArray()
        {
            return ToDoubleArray(Array());
        }

        #endregion
    }
    #endregion  

}


Measured memory_bytes: 15312