#include <bits/stdc++.h>

using namespace std;

const int N = 2e5 + 10;

int fa[N], a[N], sz[N], n;

int find(int rt) {
  return rt == fa[rt] ? rt : fa[rt] = find(fa[rt]);
}

int main() {
  // freopen("in.txt", "r", stdin);
  // freopen("out.txt", "w", stdout);
  scanf("%d", &n);
  for (int i = 1; i <= n; i++) {
    scanf("%d", &a[i]);
  }
  for (int i = 1; i < N; i++) {
    fa[i] = i, sz[i] = 1;
  }
  for (int i = 1; n - i + 1 > i; i++) {
    int u = find(a[i]), v = find(a[n - i + 1]);
    if (u != v) {
      fa[u] = v;
      sz[v] += sz[u];
    }
  }
  int ans = 0;
  for (int i = 1; i < N; i++) {
    if (fa[i] == i) {
      ans += sz[i] - 1;
    }
  }
  printf("%d\n", ans);
  return 0;
}
#include <bits/stdc++.h>
using namespace std;

template <typename A, typename B>
string to_string(pair<A, B> p);
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p);
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
 
string to_string(const string& s) {
  return '"' + s + '"';
}
 
string to_string(const char* s) {
  return to_string((string) s);
}
 
string to_string(bool b) {
  return (b ? "true" : "false");
}
 
string to_string(vector<bool> v) {
  bool first = true;
  string res = "{";
  for (int i = 0; i < static_cast<int>(v.size()); i++) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(v[i]);
  }
  res += "}";
  return res;
}
 
template <size_t N>
string to_string(bitset<N> v) {
  string res = "";
  for (size_t i = 0; i < N; i++) {
    res += static_cast<char>('0' + v[i]);
  }
  return res;
}
 
template <typename A>
string to_string(A v) {
  bool first = true;
  string res = "{";
  for (const auto &x : v) {
    if (!first) {
      res += ", ";
    }
    first = false;
    res += to_string(x);
  }
  res += "}";
  return res;
}
 
template <typename A, typename B>
string to_string(pair<A, B> p) {
  return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
 
template <typename A, typename B, typename C>
string to_string(tuple<A, B, C> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ")";
}
 
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
  return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " + to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
 
void debug_out() { cerr << endl; }
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
  cerr << " " << to_string(H);
  debug_out(T...);
}
#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

#define fi first
#define se second
#define pb push_back
#define mod(n,k) ( ( ((n) % (k)) + (k) ) % (k))
#define forn(i,a,b) for(int i = a; i < b; i++)
#define forr(i,a,b) for(int i = a; i >= b; i--)
#define all(x) (x).begin(), (x).end()

typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> ii;
typedef vector<int> vi;
typedef vector<ii> vii;

const ll mod = 1e9+7;
ll mul(ll a,ll b){return ((a%mod)*(b%mod))%mod;}
ll sum(ll a,ll b){return ((a%mod)+(b%mod))%mod;}
ll sub(ll a,ll b){return ((a%mod)-(b%mod))%mod;}
ll power(ll a,ll b){
	ll res = 1;
	while(b){
		if(b&1)res = mul(res,a);
		b >>= 1;
		a = mul(a,a);
	}
	return res;
}


int main(){
	ios_base::sync_with_stdio(0); cin.tie(0);
	int N; cin >> N;
	vii A(N);
	forn(i,0,N){
		ll a,b; cin >> a >> b;
		ll sum = a+b;
		A[i].fi = sum;
		A[i].se = a;
	}
	sort(all(A),[&](ii a,ii b){
		ll s1 = a.fi+a.se;
		ll s2 = b.fi+b.se;
		return s1 < s2;
	});
	ll tot = 0;
	forn(i,0,N)tot += A[i].se;
	int res = 0;
	ll act = 0;
	forr(i,N-1,0){
		act += A[i].fi;
		tot -= A[i].se;
		if(act > tot)break;
		res++;
	}
	cout << res+1 << '\n';
	return 0;
}
/*
__builtin_mul_overflow(x,y,&x)
-fsplit-stack
*/
