15. Write a program to demonstrate Milne Simpson Method.

        /*Program to execute Milne Simpson Method*/
	#include <stdio.h>
	#include <conio.h>
	#include <math.h>
	float dif(float x, float y)
	{
	    return x + y;
	}
	float pred(float y0, float h, float f1, float f2, float f3)
	{
	    return y0 + 4 * h * (2 * f1 - f2 + 2 * f3) / 3;
	}
	float corr(float y2, float h, float f2, float f3, float f4)
	{
	    return y2 + h * (f2 + 4 * f3 + f4) / 3;
	}
	void main()
	{
	    float x, h, x0, x1, y0, y1, y2, y3, y4, x4, f1, f2, f3, f4;
	    float aerr, yc, yc1;
	    printf("Enter the values of x, h, x0, aerr: ");
	    scanf("%f%f%f%f", &x, &h, &x0, &aerr);
	    printf("Enter the values of y0, y1, y2, y3: ");
	    scanf("%f%f%f%f", &y0, &y1, &y2, &y3);
	    while (x4 < x)
	    {
	        f1 = dif(x0 + h, y1);
	        f2 = dif(x0 + 2 * h, y2);
	        f3 = dif(x0 + 3 * h, y3);
	        printf("\n\nf1=%f\tf2=%f\tf3=%f\n", f1, f2, f3);
	        y4 = pred(y0, h, f1, f2, f3);
	        x4 = x0 + 4 * h;
	        f4 = dif(x4, y4);
	        printf("\nPredicator values:");
	        printf("\n\ty=%f\tf4=%f", y4, f4);
	        y4 = corr(y2, h, f2, f3, f4);
	        f4 = dif(x4, y4);
	        printf("\nCorrector values:");
	        printf("\n\ty=%f\tf4=%f", y4, f4);
	        yc = corr(y2, h, f2, f3, f4);
	        f4 = dif(x4, yc);
	        printf("\n\ty=%f\tf4=%f", yc, f4);
	        while (fabs(yc - y4) > aerr)
	        {
	            y4 = yc;
	            yc = corr(y2, h, f2, f3, f4);
	            f4 = dif(x4, yc);
	            printf("/n/ty=%f\tf4=%f", yc, f4);
	        }
	        x0 += h;
	        printf("\nValues of y=%f, when x=%f", yc, x4);
	        y0 = y1;
	        y1 = y2;
	        y2 = y3;
	        y3 = y4;
	    }
	    getch();
	}