Problem:
Score : 100 points

Problem Statement

Cat Snuke is learning to write characters.
Today, he practiced writing digits 1 and 9, but he did it the other way around.

You are given a three-digit integer n written by Snuke.
Print the integer obtained by replacing each digit 1 with 9 and each digit 9 with 1 in n.

Constraints

111 \leq n \leq 999

n is an integer consisting of digits 1 and 9.

Input

Input is given from Standard Input in the following format:

n

Output

Print the integer obtained by replacing each occurrence of 1 with 9 and each occurrence of 9 with 1 in n.

Sample Input 1

119

Sample Output 1

991

Replace the 9 in the ones place with 1, the 1 in the tens place with 9 and the 1 in the hundreds place with 9. The answer is 991.

Sample Input 2

999

Sample Output 2

111

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using BitArray = System.Collections.BitArray;
using BigInteger = System.Numerics.BigInteger;

namespace AtCoderProject
{
    public class Program
    {
        public object Calc()
        {
            return consoleReader.String().Replace('1', 'a').Replace('9', '1').Replace('a', '9');
        }

        IEnumerable<int> GetYakusu(int n)
        {
            int amari;
            var sqrt = (int)Math.Sqrt(n);
            for (int i = 1; i <= sqrt; i++)
            {
                var d = Math.DivRem(n, i, out amari);
                if (amari == 0)
                {
                    yield return i;
                    if (i != d)
                        yield return d;
                }
            }
        }

        public const int mod = 1000000007;
        private readonly ConsoleReader consoleReader;
        public Program() : this(new ConsoleReader()) { }
        public Program(ConsoleReader consoleReader) { this.consoleReader = consoleReader; }
        static void Main() => Console.WriteLine(new Program().Calc());
        public static string MultiLine<T>(IEnumerable<T> source) => string.Join("\n", source);
    }

    public class ConsoleReader { public virtual string String() => Console.ReadLine(); public int Int32() => int.Parse(String()); public long Int64() => long.Parse(String()); public ulong UInt64() => ulong.Parse(String()); public double Double() => double.Parse(String()); public string[] Split() => String().Split().ToArray(); public int[] SplitInt32() => String().Split().Select(int.Parse).ToArray(); public long[] SplitInt64() => String().Split().Select(long.Parse).ToArray(); public ulong[] SplitUInt64() => String().Split().Select(ulong.Parse).ToArray(); public double[] SplitDouble() => String().Split().Select(double.Parse).ToArray(); public IEnumerable<string> Repeat(int count) { for (int i = 0; i < count; i++) yield return String(); } public IEnumerable<int> RepeatInt32(int count) { for (int i = 0; i < count; i++) yield return Int32(); } public IEnumerable<long> RepeatInt64(int count) { for (int i = 0; i < count; i++) yield return Int64(); } public IEnumerable<string[]> RepeatSplit(int count) { for (int i = 0; i < count; i++) yield return Split(); } public IEnumerable<int[]> RepeatSplitInt32(int count) { for (int i = 0; i < count; i++) yield return SplitInt32(); } }
}