[백준] 1065번 : 한수 - C#

https://www.acmicpc.net/problem/1065

using System;

class Program
{
    static void Main() {
        string s=Console.ReadLine();
        int x=int.Parse(s);
        int count=99;
        if(x<100) Console.Write(x);
        else{
            for(int i=100;i<=x;i++){
                int a=i%10;
                int b=(i/10)%10;
                int c=(i/10)/10;
                if(c-b==b-a) count++;
        }
        Console.WriteLine(count);
        }
    }
}