Problem:
Score : 100 points

Problem Statement

Snuke has N integers: 1,2,\ldots,N.
He will choose K of them and give those to Takahashi.

How many ways are there to choose K consecutive integers?

Constraints

All values in input are integers.

1 \leq K \leq N \leq 50

Input

Input is given from Standard Input in the following format:

N K

Output

Print the answer.

Sample Input 1

3 2

Sample Output 1

2

There are two ways to choose two consecutive integers: (1,2) and (2,3).

Sample Input 2

13 3

Sample Output 2

11

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()
        {
            var line = consoleReader.SplitInt32();
            var N = line[0];
            var K = line[1];

            return N - K + 1;
        }

        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(); }
    }
}