Problem:
Score : 100 points

Problem Statement

On some day in January 2018, Takaki is writing a document. The document has a column where the current date is written in yyyy/mm/dd format. For example, January 23, 2018 should be written as 2018/01/23.

After finishing the document, she noticed that she had mistakenly wrote 2017 at the beginning of the date column. Write a program that, when the string that Takaki wrote in the date column, S, is given as input, modifies the first four characters in S to 2018 and prints it.

Constraints

S is a string of length 10.

The first eight characters in S are 2017/01/.

The last two characters in S are digits and represent an integer between 1 and 31 (inclusive).

Input

Input is given from Standard Input in the following format:

S

Output

Replace the first four characters in S with 2018 and print it.

Sample Input 1

2017/01/07

Sample Output 1

2018/01/07

Sample Input 2

2017/01/31

Sample Output 2

2018/01/31

Solution in C# (Mono 4.6.2.0) (judge verdict: Runtime Error)

using System;
using System.Collections.Generic;

namespace AtCoder0106_4
{
    class Program
    {
        static void Main(string[] args)
        {
            string[] input = Console.ReadLine().Split(' ');
            int n = int.Parse(input[0]);
            int h = int.Parse(input[1]);
            List<int> a = new List<int>();
            List<int> b = new List<int>();
            int maxa = 0;

            for (int i = 0; i < n; i++)
            {
                string[] ken = Console.ReadLine().Split(' ');
                a.Add(int.Parse(ken[0]));
                b.Add(int.Parse(ken[1]));
                if (maxa < int.Parse(ken[0]))
                {
                    maxa = int.Parse(ken[0]);
                }
            }

            int nokorih = h;
            int num = 0;
            for (int i = 0; i < n; i++){
                if(nokorih < 0){
                    break;
                }
                if(maxa < b[i]){
                    nokorih -= b[i];
                    num++;
                }
            }

            if(nokorih < 0){
                // do nothing
            }else if(nokorih%maxa == 0){
                num += nokorih / maxa;
            }else{
                num += nokorih / maxa + 1;
            }

            Console.WriteLine(num);
        }
    }
}