/* Generated by the powerful Sio Tool
 * You can download the binary file here: https://github.com/Arapak/sio-tool
 * Author:  (Karol Bonat)
 * Time of creation: 2024-03-20 09:51:30
 * Notes: 
**/

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

constexpr int MAXN = 106;

int n;
int A[MAXN];
int C[MAXN];

int per[MAXN];

bool usd[MAXN];

bool odw[MAXN];
bool cur[MAXN];
int msk;

// int ile_cyc;
bool DFS(int i){
	if(cur[i]) return 1;// Error
	if(odw[i]){
		return 0;// No Error
	}
	if(((1<<i) & msk ) == 0) return 0; // No error
	cur[i]=1;
	odw[i]=1;
	if(DFS(A[i])) return 1;
	cur[i]=0;
	return 0;
}

bool verify(vector<int> & act){
	for(int i = 0; i <= n; i++){
		odw[i] = 0;
		cur[i] = 0;
	}
	for(auto st : act){
		int i = st;
		if(odw[i]) continue;
		if(DFS(i)) return 1;
	}
	return 0;
	// if(msk < (1<<n)-1) return ile >= 2;
	// return ile >= ;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> n;
	for(int i = 0; i < n; i++){
		cin >> A[i] >> C[i];
		A[i]--;
	}
	ll res = LLONG_MAX;
	//Check if input is correct
	int t = 0;
	int cnt = 0;
	while(!odw[t]){
		odw[t] = 1;
		t = A[t];
		cnt++;
	}
	if(cnt == n && t == 0){
		cout << 0 << '\n';
		return 0;
	}
	for(msk = 0; msk < (1 << n)-1; msk++){
		ll r = 0;
		for(int i = 0; i <= n; i++){
			usd[i] = 0;
		}
		vector<int> act;
		for(int i = 0; i < n; i++){
			if((1<<i) & msk){
				if(usd[A[i]]) r=LLONG_MAX;
				usd[A[i]]=1;
				act.push_back(i);
			}
		}
		if(r>0) continue;
		if( verify(act)) continue;

		//Cycklon B

		for(int i = 0; i < n; i++){
			if(!(((1<<i) & msk)>0)){
				r+=C[i];
			}
		}

		res = min(res, r);
	}
	cout << res << '\n';
	return 0;
}