Problem:
Score : 200 points

Problem Statement

Given are 1-digit positive integers a and b. Consider these two strings: the concatenation of b copies of the digit a, and the concatenation of a copies of the digit b. Which of these is lexicographically smaller?

Constraints

1 \leq a \leq 9

1 \leq b \leq 9

a and b are integers.

Input

Input is given from Standard Input in the following format:

a b

Output

Print the lexicographically smaller of the two strings. (If the two strings are equal, print one of them.)

Sample Input 1

4 3

Sample Output 1

3333

We have two strings 444 and 3333. Between them, 3333 is the lexicographically smaller.

Sample Input 2

7 7

Sample Output 2

7777777

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

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.Contracts;
using System.Linq;
using System.Text;

public class Test152_b
{

        /// <summary>
        /// https://atcoder.jp/contests/abc152/tasks/abc152_b
        /// </summary>
        public static void Main()
        {
            string[] ss = Console.ReadLine().Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);

            int a = int.Parse(ss[0]);
            int b = int.Parse(ss[1]);

            //整数 a を b 回繰り返してできる文字列と
            //整数 b を a 回繰り返してできる文字列と
            StringBuilder sbA = new StringBuilder();
            StringBuilder sbB = new StringBuilder();
            for(int i=0;i<a;i++)
            {
                sbA.Append(a.ToString());
            }
            for (int i = 0; i < a; i++)
            {
                sbB.Append(b.ToString());
            }

            // 辞書順で小さい方を答えてください。
            if (string.Compare(sbA.ToString(), sbB.ToString()) < 0)
            {
                Console.WriteLine(sbA.ToString());
            }
            else
            {
                Console.WriteLine(sbB.ToString());
            }
        }
}