#include <stdio.h>
#include <math.h>
double func(double x)
{
return exp(x);
}
void main(){
double h,x;
h=0.1;
printf("Input x: ");
scanf("%lf",&x);
for(;fabs((func(x+h)-func(x))/h)>pow(10,-5);)
{
h=h-0.01;
}
printf("h=%.4lf\n",h);
getch();
}