made in China

#include <iostream>
#include <vector>
#include <map>
#include <algorithm>

using namespace std;

int main() {
    int n;
    cin >> n;
    
    vector<pair<int, long long>> cows(n); // (种族, 坐标)
    
    for (int i = 0; i < n; ++i) {
        cin >> cows[i].first >> cows[i].second;
    }
    
    // Step 1: Sort cows based on their coordinates
    sort(cows.begin(), cows.end(), [](const pair<int, long long>& a, const pair<int, long long>& b) {
        return a.second < b.second;
    });
    
    // Step 2: Initialize balance map and other variables
    map<int, int> balance_map; // balance -> first occurrence index
    balance_map[0] = -1; // balance 0 at index -1 (before the start)
    
    int balance = 0;
    long long max_length = 0;
    
    // Step 3: Traverse sorted cows
    for (int i = 0; i < n; ++i) {
        if (cows[i].first == 0) { // Breed 0
            balance--;
        } else { // Breed 1
            balance++;
        }
        
        // Check if this balance has been seen before
        if (balance_map.find(balance) != balance_map.end()) {
            // Calculate the length of the balanced interval
            int start_index = balance_map[balance];
            long long interval_length = cows[i].second - cows[start_index + 1].second; // Get the coordinates
            max_length = max(max_length, interval_length);
        } else {
            // If not seen, record the first index of this balance
            balance_map[balance] = i;
        }
    }
    
    // Output the result
    cout << max_length << endl;
    return 0;
}

//#include<bits/stdc++.h>
using namespace std;
const int N=5e5+10;
struct node
{
	int x,id;
}a[N];
int cmp(node a,node b)
{
	return a.x<b.x;
}
int main ()
{
	int n,s[N]={},ans=0;
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		cin>>a[i].id>>a[i].x;
		if(a[i].id==0)
		{
			a[i].id=-1;
		}
	}
	sort(a+1,a+n+1,cmp);
	for(int i=1;i<=n;i++)
	{
		s[i]=s[i-1]+a[i].id;
	} 
	for(int i=1;i<=n;i++)
	{
		for(int j=i+1;j<=n;j++)
		{
			if(s[i-1]==s[j])
			{
				ans=max(ans,a[j].x-a[i].x);
			} 
		}
	}
	cout<<ans;
}