#include<bits/stdc++.h>
using namespace std;
int n,k,ans,z;
int main()
{
cin>>n>>k;
for (int i=1;i<=k;i++)z+=i;
for (int i=1;i<=n-k;i++)
{
z+=k;
// cout<<z<<endl;
if (floor(sqrt(z))==sqrt(z))ans+=1;
}
cout<<ans;
return 0;
}
/**************************************************************
Problem: 1560
User: admin
Language: C++
Result: Accepted
Time:49 ms
Memory:2072 kb
****************************************************************/