Const
E=0.001;
Var
h,a,b,Jn,J2n:real;
N,i:Word;
Begin
Write('a= ');
Readln(a);
Write('b= ');
Readln(b);
N:=2;
h:=(b-a)/N;
J2n:=0;
For i:=1 to N do
J2n:=J2n+h*Cos(a+h*i-h/2);
Repeat
Jn:=J2n;
N:=N*2;
h:=(b-a)/N;
J2n:=0;
For i:=1 to N do
J2n:=J2n+h*Cos(a+h*i-h/2);
Until Abs(Jn-J2n)<=E;
Writeln(' Integral = ',J2n:0:6);
Writeln('Accurate value = ',(Sin(b)-Sin(a)):0:6);
Readln;
End.