//Yukicoder
//Q1009
//




//二次元可変配列
//vector <vector <int>> mass;
//vector <vector <int>> memo;

//#include "stdafx.h"
#include <iostream>
#include <vector>
#include <list>//list
#include <set> //tree
#include <map> //連想配列
#include <unordered_set> //hash
#include <unordered_map> //hash
#include <algorithm>
#include <iomanip>

using namespace std;
typedef unsigned long long ULL;
typedef signed long long SLL;


#define START (0)
#define RIGHT (1)
#define UP    (2)
#define LEFT  (3)
#define DOWN  (4)

#define DATA_MAX (1000000)
#define FMAX(a,b)  ((a)>(b)?(a):(b))
#define FMIX(a,b)  ((a)<(b)?(a):(b))


vector <vector <SLL>> memo2;
vector<SLL> memo1;
vector<SLL> c;
vector<SLL> K;
vector<SLL> dp;

SLL N, D, H ,A, B;



int main()
{
	double a, b, y, totalS=0.0F;

	//float jf = 0.0f;
	//float min = INFINITY;

	cin >> a;
	cin >> b;

	for (double x = a; x <= b; x+=0.00001f)
	{

		y = abs(x - a) * abs(x - b);
		totalS += y;
	}

	cout << totalS/100000 << endl;

	//printf("%.6lf", totalS/100000.0f);


	//getchar();
	return 0; //end
}