using System;

using System.Collections.Generic;

​

public class Program

    {

​

        static double I =

            0.5 * (Math.Log( 56 ) - Math.Log( 2 )) -

            21 * (Math.Log( 8.0 / 7.0 ) - Math.Log( 2 )) / 2;

​

        static double func ( double t )

        {

            return (t + 12) / (t * t + 3 * t + 2);

        }

​

        static double m_LeftRectangles ( double a, double b, double h )

        {

            int k = 1;

            if (a > b)

            {

                double c = a;

                a = b;

                b = c;

                k = -1;

            }

            double R = 0;

            for (double i = a; i < b; i += h)

                R += func( i );

            return k * R * h;

        }

​

        static double m_Runge ( double a, double b, double h )

        {

            return 2 * m_LeftRectangles( a, b, h / 2 ) - m_LeftRectangles( a, b, h );

        }

​

        static Tuple<double, double, double> get_R ( double a, double b, double h )

        {

            return Tuple.Create( 

                Math.Abs( I - m_LeftRectangles( a, b, h ) ),

                Math.Abs( I - m_LeftRectangles( a, b, h/2 ) ),

                Math.Abs( I - m_Runge( a, b, h ) ) );

        }

​

        public static void Main ( string[] args )

        {

            const double a = 0;

            const double b = 6;

            const uint MaxN = 24;

            Console.WriteLine( "I = "+ I );

            Console.WriteLine( get_R( a, b, 0.0001 ) );

            var Vec = new List<Tuple<double, double, double>>();

            for (uint i = 0; i < MaxN; i++)

                Vec.Add( get_R( a, b, (b - a) / (Math.Pow( 2.0, i )) ) );

            Console.WriteLine( Vec.Count );

            for (int i = 0; i < MaxN; i++)

                Console.WriteLine( Vec[i] );

            Console.WriteLine( "Done ! " );

​

​

    }

​

}