#include<stdio.h>
#include<stdlib.h>
#include<math.h>

#define N 1000

double integral(void);

int a,b;
double f(double x){	return (x-a)*(x-b);	}

int main()
{
	scanf("%d %d",&a,&b);
	if(a==b){
		printf("0");
	}else{
		printf("%.8f",fabs(integral()));
	}
	return 0;
}

double integral(void)
{
	double ans,x,h;
	ans=0,x=a;
	h=(double)(b-a)/N;
	for(int i=0;i<N;i++){
		ans+=f(x)*h;
		x+=h;
	}
	return ans;
}