#include <iostream>
#include <cmath>
#include <algorithm>
#include <string>
#include <vector>
#include <map>
#include <queue>
#include <stack>
#include <list>
#include <deque>
#include <set>
#include <numeric>
using namespace std;
using ll = long long;
using ld = long double;

const ll MOD = 1000000000 + 7;
const ll INF = 1e+9;
const ld PI = acos((long double)(-1));

#define no "no"
#define No "No"
#define NO "NO"
#define yes "yes"
#define Yes "Yes"
#define YES "YES"
#define next '\n'
#define sp " "
#define print(x) cout << (x) << endl;
#define rep(i, n) for(int (i) = (0); (i) < (n); (++i))
#define FOR(i, start, end) for(int (i) = (start); (i) < (end); (++i))
#define foreach(elem, _list) for(auto& (elem) : (_list))
#define view(_list) foreach(e, _list){ cout << e << sp; } cout << next
#define FAST ios::sync_with_stdio(false); cin.tie(nullptr)
#define size(s) (s).size()
#define ALL(vec) (vec).begin(), (vec).end()
#define pb(e) push_back(e)
#define EPS 0.00000001

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

int main() {
    FAST;

    double n = 100000;
    double a, b;
    cin >> a >> b;

    double delta = (b - a) / n;

    double area = 0;
    for(double i = a; i < b; i += delta){
        area += delta * abs(fx(i, a, b));
    }

    print(area);
}