using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
 
namespace AtCoder
{
    static class Program_D
    {
        class Solver
        {
            int ri => sc.Integer();
            long rl => sc.Long();
            double rd => sc.Double();
            string rs => sc.Scan();
            public StreamScanner sc = new StreamScanner(Console.OpenStandardInput());
            private int[][] cell;
            private int n;

            private int Calc(int num, int start, int end, int keta)
            {
                if (keta == 1)
                {
                    if (start != end) return 0;
                    return start <= num ? 1 : 0;
                } 
                int maxNum = start;
                int minNum = start;
                for (int i = 1; i < keta - 1; ++i)
                {
                    maxNum *= 10;
                    maxNum += 9;
                    minNum *= 10;
                }
                maxNum *= 10;
                maxNum += end;
                minNum *= 10;
                minNum += end;

                if (keta == 2)
                {
                    var result = num >= maxNum ? 1 : 0;
                    return result;
                }
                if (num >= maxNum)
                {
                    // 9, 99, 999,...
                    int result = 1;
                    for (int i = 0; i < keta - 2; ++i)
                    {
                        result *= 10;
                    }
                    return result;
                }
                if (num < minNum)
                {
                    return 0;
                }
                {
                    var result = 1 + (num - minNum) / 10;
                    return result;
                }

            }

            private int CalcForOneCell(int start, int end)
            {
                int count = 0;
                for (int keta = 1; keta < 10; ++keta)
                {
                    var c = Calc(n, start, end, keta);
                    if (keta>1 && c == 0)
                    {
                        //Wl($"({start}-{end}), {count}");
                        return count;
                    }
                    count += c;
                }
                return count;
            }

            // 152-D HandStand
            public void Solve()
            {
                n = ri;
                //var tests = new[]
                //{
                //    new[] {2004, 1, 2, 1},
                //    new[] {2004, 1, 1, 1},
                //    new[] {2004, 1, 1, 2},
                //    new[] {2004, 1, 1, 4},
                //    new[] {1991, 1, 1, 4},
                //    new[] {1991, 1, 2, 4},
                //    new[] {1990, 1, 1, 4},
                //};
                //foreach (var test in tests)
                //{
                //    var calc = Calc(test[0], test[1], test[2], test[3]);
                //    Wl(string.Format($"Calc({test[0]}, {test[1]}, {test[2]}, {test[3]}) = {calc}"));
                //}

                cell = new int[10][];
                for (int i = 0; i < 10; ++i)
                {
                    cell[i] = new int[10];
                }

                for (int start = 1; start <= 9; ++start)
                {
                    for (int end = 1; end <= 9; ++end)
                    {
                        cell[start][end] = CalcForOneCell(start, end);
                    }
                }

                // start-end, end-startの乗算&加算
                long result = 0;
                for (int start = 1; start <= 9; ++start)
                {
                    for (int end = 1; end <= 9; ++end)
                    {
                        result += cell[start][end] * cell[end][start];
                    }
                }
                Wl(result);

            }




            // ----------------------------------------------------------------------------
            static public void Swap<T>(ref T a, ref T b) { var tmp = a; a = b; b = tmp; }


            string Rl()
            {
                return Console.ReadLine();
            }
            void Wl(UInt64 val)
            {
                Console.WriteLine(val);
            }
            void Wl(Int64 val)
            {
                Console.WriteLine(val);
            }
            void Wl(uint val)
            {
                Console.WriteLine(val);
            }
            void Wl(int val)
            {
                Console.WriteLine(val);
            }
            void Wl(double val)
            {
                Console.WriteLine(val);
            }
            void Wl(string mes)
            {
                Console.WriteLine(mes);
            }
            public int Int()
            {
                return int.Parse(Console.ReadLine());
            }

            public int[] Ints(int subtract)
            {
                return Console.ReadLine().Split(' ').Select(s => int.Parse(s) - subtract).ToArray();
            }
            public Int64[] Int64s(Int64 subtract)
            {
                return Console.ReadLine().Split(' ').Select(s => Int64.Parse(s) - subtract).ToArray();
            }
            public UInt64[] UInt64s(UInt64 subtract)
            {
                return Console.ReadLine().Split(' ').Select(s => UInt64.Parse(s) - subtract).ToArray();
            }


        }



        static void Main(string[] args)
        {
            //Console.SetOut(new Printer(Console.OpenStandardOutput()) { AutoFlush = false });
            new Solver().Solve();
            //Console.Out.Flush();
        }
    }

    public class Printer : StreamWriter
    {
        public override IFormatProvider FormatProvider => CultureInfo.InvariantCulture;
        public Printer(Stream stream) : base(stream, new UTF8Encoding(false, true)) { }
    }

    public class StreamScanner
    {
        public StreamScanner(Stream stream) { str = stream; }

        public readonly Stream str;
        private readonly byte[] buf = new byte[1024];
        private int len, ptr;
        public bool isEof = false;

        private byte read()
        {
            if (isEof) return 0;
            if (ptr >= len)
            {
                ptr = 0;
                if ((len = str.Read(buf, 0, 1024)) <= 0)
                {
                    isEof = true;
                    return 0;
                }
            }
            return buf[ptr++];
        }

        public char Char()
        {
            byte b = 0;
            do b = read(); while ((b < 33 || 126 < b) && !isEof);
            return (char)b;
        }
        public string Scan()
        {
            var sb = new StringBuilder();
            for (var b = Char(); b >= 33 && b <= 126; b = (char)read()) sb.Append(b);
            return sb.ToString();
        }
        public string ScanLine()
        {
            var sb = new StringBuilder();
            for (var b = Char(); b != '\n' && b != 0; b = (char)read()) if (b != '\r') sb.Append(b);
            return sb.ToString();
        }
        public long Long() { return isEof ? long.MinValue : long.Parse(Scan()); }
        public int Integer() { return isEof ? int.MinValue : int.Parse(Scan()); }
        public double Double() { return isEof ? double.NaN : double.Parse(Scan(), CultureInfo.InvariantCulture); }
    }

    struct ModInt
    {
        const int MOD = 1000000007;
        long Data;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public ModInt(long data) { if ((Data = data % MOD) < 0) Data += MOD; }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static implicit operator long(ModInt modInt) => modInt.Data;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static implicit operator ModInt(long val) => new ModInt(val);
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static ModInt operator +(ModInt a, ModInt b)
        {
            long res = a.Data + b.Data;
            return new ModInt() { Data = res >= MOD ? res - MOD : res };
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static ModInt operator +(ModInt a, long b) => a.Data + b;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static ModInt operator -(ModInt a, ModInt b)
        {
            long res = a.Data - b.Data;
            return new ModInt() { Data = res < 0 ? res + MOD : res };
        }
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static ModInt operator -(ModInt a, long b) => a.Data - b;
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static ModInt operator *(ModInt a, ModInt b) => new ModInt() { Data = a.Data * b.Data % MOD };
        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public static ModInt operator /(ModInt a, ModInt b) => a.Data * GetInverse(b);

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        public override string ToString() => Data.ToString();

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
        static long GetInverse(long a)
        {
            long div;
            long p = MOD;
            long x1 = 1, y1 = 0, x2 = 0, y2 = 1;
            while (true)
            {
                if (p == 1) return x2;
                div = a / p;
                x1 -= x2 * div;
                y1 -= y2 * div;
                a %= p;
                if (a == 1) return x1;
                div = p / a;
                x2 -= x1 * div;
                y2 -= y1 * div;
                p %= a;
            }
        }
    }

}

Measured memory_bytes: 27408