#include<stdio.h>

#define f(x,y)=x*y
void main ()
{
    float a,b,x,y,t,k,h;
    clrscr();
    printf("enter x0,y0,h,and xn");
    scanf("%f%f%f%f,&a,&b,&h,&t");
    x=a;
    y=b;
    while(x<t)
    {
        k=h*f(x,y);
        y=y+k;
        x=x+h;
        printf("x=%f\ty=%%f\n,x,y");
        getch();
    }
}