#include<bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;

ld a, b;

ld f(ld x) {
    return (x - a) * (x - b);
}

int main()
{
    cin >> a >> b;
    ld ans = 0;
    for(ld i = a; i <= b; i += 0.00001) {
        ans += -f(i)*0.00001;
    }
    cout << fixed <<setprecision(12) << ans << endl; 
}