int main()
{
int n, m, p;
cin >> n >> m >> p;
if(m == n)
{
cout << 1;
return 0;
}
m -= (n + 1);
int ans = 2;
int l = max(1, p - 1);
int r = min(n, p + 1);
while(true)
{
int val = r - l + 1;
if(m < val)
break;
m -= val;
++ ans;
l = max(1, l - 1);
r = min(n, r + 1);
}
cout << ans;
}
