Problem:
Score : 200 points

Problem Statement

Find the number of palindromic numbers among the integers between A and B (inclusive).
Here, a palindromic number is a positive integer whose string representation in base 10 (without leading zeros) reads the same forward and backward.

Constraints

10000 \leq A \leq B \leq 99999

All input values are integers.

Input

Input is given from Standard Input in the following format:

A B

Output

Print the number of palindromic numbers among the integers between A and B (inclusive).

Sample Input 1

11009 11332

Sample Output 1

4

There are four integers that satisfy the conditions: 11011, 11111, 11211 and 11311.

Sample Input 2

31415 92653

Sample Output 2

612

Solution in C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace atcoder_問題5_B2問目
{
    class Program
    {
        static void Main(string[] args)
        {
            //問題5
            string[] input = Console.ReadLine().Split(' ');
            int c = Convert.ToInt32(input[0]);
            int d = Convert.ToInt32(input[1]);
            int sum = 0;
            for (int e = c; e < d; ++e)
            {
                string f = Convert.ToString(e);
                int num = e;
                int rev = 0;
                while (num > 0)
                {
                    rev = rev * 10 + num % 10;
                    num /= 10;
                }
                string revstr = rev.ToString();
                bool check = f.Contains(revstr);
                int ok = e - Convert.ToInt32(revstr);
                if (check)
                {
                    if (ok == 0)
                    {
                        sum = sum + 1;
                    }
                }
            }
            Console.WriteLine(sum);

        }
    }
}