#include<iostream>
#include<math.h>
#include<stdio.h>
using namespace std;

int main()
{
#ifndef ONLINE_JUDGE
    freopen ("input.txt", "r", stdin);
    freopen ("output.txt", "w", stdout);
#endif

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    unsigned long long a,b;
    cin >> a >> b;
    if ((a == b) && (sqrt(a) == ((long long) sqrt(a))))
    {
        cout << 1;
        return 0;
    }
    cout << (unsigned long long) (sqrt(b) - sqrt(a) + 1);
    return 0;
}