import java.util.*;
import java.io.*;


public class Main{
    public static void main(String[] args){
        FastScanner sc = new FastScanner();
        PrintWriter out = new PrintWriter(System.out);
        int N = sc.nextInt();
        int result = 0;
        int[][] t = new int[10][10];
        for(int i=0;i<10;i++){
            for(int j=0;j<10;j++){
                t[i][j] = 0;
            }
        }
        for(int i=1;i<=N;i++){
            int f = i/(getDigit(i));
            int s = i%10;
            t[f][s]+=1;
        }
        for(int i=1;i<=N;i++){
            result += t[i%10][i/(getDigit(i))];
        }



        out.println(result);
        out.flush();
    }

    static int getDigit(int a){
        int res = 1;
        while(a>0){
            if(a/10!=0){
                res = res*10;
            }
            a /= 10;
        }
        return res;
    }
        
}
class Pair{
    int id1,id2;
    public Pair(int a, int b){
        this.id1 = a;
        this.id2 = b;
    }
    int getFirst(){
        return this.id1;
    }
    int getSecond(){
        return this.id2;
    }
}



class FastScanner {
    private final InputStream in = System.in;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;
    private boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        }else{
            ptr = 0;
            try {
                buflen = in.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }
    private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
    private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
    public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
    public String next() {
        if (!hasNext()) throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while(isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }
    public long nextLong() {
        if (!hasNext()) throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while(true){
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            }else if(b == -1 || !isPrintableChar(b)){
                return minus ? -n : n;
            }else{
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }
    public int nextInt() {
        long nl = nextLong();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
        return (int) nl;
    }
    public double nextDouble() { return Double.parseDouble(next());}
}

Measured memory_bytes: 22996