using System;
using System.Linq;

class A
{
	static int[] Read() => Array.ConvertAll(Console.ReadLine().Split(), int.Parse);
	static (int, int) Read2() { var a = Read(); return (a[0], a[1]); }
	static void Main() => Console.WriteLine(Solve());
	static object Solve()
	{
		var (a, b) = Read2();
		return a - b;
	}
}