Unit 5.2 Euler's Modified

#include <stdio.h>
#include<math.h>
#define f(x0,y) ((x0*x0)+y)
int  main()
{
    int i,n;
    float x0,y0,h,y1,y2,x0n;
    printf("Enter values x00, y0, h and x0n \n");
    scanf("%f %f %f %f",&x0,&y0,&h,&x0n);
    n=(x0n-x0)/h;
    for(i=0;i<n;i++)
    {
        y1 = y0+(h*(f(x0,y0)));
        do{
            y2 = y1;
            y1 = y0 + ( (h/2)*( f(x0,y0) +  f((x0+h),y2) ) ) ;
        }while(fabs((y2-y1)/y1)>0.0001);

        x0 = x0+h;
        y0 = y1;
    }

    printf("\nFinal value y(%f) = %f ",x0,y0);
    return 0;
}
/*
Enter values x0, y0, h and xn
0 0.94 0.1 0.1

Final value y(0.100000) = 1.039473
*/