using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Numerics;
namespace Tasks;
public class C
{
public static void Main()
{
using var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
Console.SetOut(sw);
Solve();
Console.Out.Flush();
}
public static void Solve()
{
var N = Scanner.Scan<int>();
var iceCreams = new (int N, long S)[N];
var S = new Dictionary<long, Dictionary<int, int>>();
var queue = new PriorityQueue<(int F, long S), long>();
for (var i = 0; i < N; i++)
{
var (f, s) = Scanner.Scan<int, long>();
iceCreams[i] = (f, s);
queue.Enqueue((f, s), -s);
}
var count = new int[N + 1];
var same = new long[N + 1];
long d = 0;
long df = -1;
var flag = false;
while (queue.TryDequeue(out var top, out _))
{
var (f, s) = top;
if (!flag)
{
if (df == -1)
{
d = s;
df = f;
}
else if (df != f)
{
d += s;
flag = true;
}
}
if (count[f] == 0)
{
count[f]++;
same[f] += s;
}
else if (count[f] == 1)
{
count[f]++;
same[f] += s / 2;
}
}
var answer = d;
for (var i = 0; i <= N; i++)
{
answer = Math.Max(answer, same[i]);
}
Console.WriteLine(answer);
}
public static class Scanner
{
public static T Scan<T>() where T : IConvertible => Convert<T>(ScanStringArray()[0]);
public static (T1, T2) Scan<T1, T2>() where T1 : IConvertible where T2 : IConvertible
{
var input = ScanStringArray();
return (Convert<T1>(input[0]), Convert<T2>(input[1]));
}
public static (T1, T2, T3) Scan<T1, T2, T3>() where T1 : IConvertible where T2 : IConvertible where T3 : IConvertible
{
var input = ScanStringArray();
return (Convert<T1>(input[0]), Convert<T2>(input[1]), Convert<T3>(input[2]));
}
public static (T1, T2, T3, T4) Scan<T1, T2, T3, T4>() where T1 : IConvertible where T2 : IConvertible where T3 : IConvertible where T4 : IConvertible
{
var input = ScanStringArray();
return (Convert<T1>(input[0]), Convert<T2>(input[1]), Convert<T3>(input[2]), Convert<T4>(input[3]));
}
public static (T1, T2, T3, T4, T5) Scan<T1, T2, T3, T4, T5>() where T1 : IConvertible where T2 : IConvertible where T3 : IConvertible where T4 : IConvertible where T5 : IConvertible
{
var input = ScanStringArray();
return (Convert<T1>(input[0]), Convert<T2>(input[1]), Convert<T3>(input[2]), Convert<T4>(input[3]), Convert<T5>(input[4]));
}
public static (T1, T2, T3, T4, T5, T6) Scan<T1, T2, T3, T4, T5, T6>() where T1 : IConvertible where T2 : IConvertible where T3 : IConvertible where T4 : IConvertible where T5 : IConvertible where T6 : IConvertible
{
var input = ScanStringArray();
return (Convert<T1>(input[0]), Convert<T2>(input[1]), Convert<T3>(input[2]), Convert<T4>(input[3]), Convert<T5>(input[4]), Convert<T6>(input[5]));
}
public static IEnumerable<T> ScanEnumerable<T>() where T : IConvertible => ScanStringArray().Select(Convert<T>);
private static string[] ScanStringArray()
{
var line = Console.ReadLine()?.Trim() ?? string.Empty;
return string.IsNullOrEmpty(line) ? Array.Empty<string>() : line.Split(' ');
}
private static T Convert<T>(string value) where T : IConvertible => (T)System.Convert.ChangeType(value, typeof(T));
}
}