#include <bits/stdc++.h>
#define file(name) freopen(name".inp" , " r " , stdin);freopen(name".out" , " w " , stdout);
#define faster ios_base :: sync_with_stdio(false) ; cin.tie(0) ; cout.tie(0) ;
#define pii pair < int , int >
#define fi first
#define se second
#define mii map< int , int>
#define reset(a,val) memset(a ,val , sizeof(a) )
#define count_bit(i) __builtin_popcountll(i)
#define mask(i) ((1LL << (i)))
#define status(x, i) (((x) >> (i)) & 1)
#define set_on(x, i) ((x) | mask(i))
#define set_off(x, i) ((x) & ~mask(i))
#define endl '\n'
#define ll long long
#define double long double
const int maxn = 1e6 + 6;
const int mod= 1e9 + 7;
const ll INFLL= 3e18 + 5;
const int INF = 1e9 + 5 ;
const int LOG = 20 ;
template <class T> inline T sqr(T x) { return x * x; };
template <class T> inline int Power(T x, int y)
{ if (!y) return 1; if (y & 1) return sqr(Power(x, y / 2)) % mod * x % mod; return sqr(Power(x, y / 2)) % mod; }
template<class T> bool minimize(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool maximize(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
inline int gcd(int x, int y)
{ return y ? gcd(y , x % y) : x;}
inline int lcm(int x, int y) { return x * y / gcd(x, y); }
using namespace std;
double calc(double ax , double ar , double bx)
{
return (ax - bx) * (ax - bx) / (4.0 * ar);
}
int n;
stack<pair<double, double>> s;
void solve()
{
cin >> n ;
for (int i = 1 ; i <= n ; ++i)
{
double x , r ; cin >> x >> r;
double maxr = r;
while (!s.empty())
{
minimize(maxr , calc(s.top().fi , s.top().se , x));
if (maxr >= s.top().se)
{
s.pop();
}
else break;
}
s.push({x , maxr});
cout << setprecision(3) << fixed << maxr << endl;
}
}
int32_t main()
{
faster;
// file("txt");
// int t ; cin >> t ; while (t--)
solve();
return 0;
}
