# Yukicoder No.180 美しいWhitespace (2)

,

http://yukicoder.me/problems/no/180

## implementation

#include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <cassert>
#define repeat(i,n) for (int i = 0; (i) < (n); ++(i))
#define whole(f,x,...) ([&](decltype((x)) y) { return (f)(begin(y), end(y), ## __VA_ARGS__); })(x)
typedef long long ll;
using namespace std;
template <class T> void setmax(T & a, T const & b) { if (a < b) a = b; }
template <class T> void setmin(T & a, T const & b) { if (b < a) a = b; }
ll binsearch(ll l, ll r, function<bool (ll)> p) { // [l, r), p is monotone
assert (l < r);
-- l; -- r; // (l, r]
while (l + 1 < r) {
ll m = (l + r + 1) / 2;
(p(m) ? r : l) = m;
}
return r; // = min { x | p(x) }
}
const ll inf = ll(1e18)+9;
int main() {
int n; cin >> n;
vector<int> a(n), b(n); repeat (i,n) cin >> a[i] >> b[i];
auto f = [&](ll x) {
ll l = inf, r = 0;
repeat (i,n) {
setmin(l, a[i] + b[i]*x);
setmax(r, a[i] + b[i]*x);
}
return r - l;
};
ll limit = *whole(max_element, a) + 2;
ll ans = binsearch(1, limit, [&](ll x) {
return f(x) <= f(x+1);
});
cout << ans << endl;
return 0;
}