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

#define QwQ330AwA return 0
#define ll long long
#define int long long

const int N = 2000005;
const int inf = 1e9;

struct Tree {
	int ls, rs;
	int val;
	int tag;
	int u, v;
	int dis;
} t[N];
int tot;
#define ls(p) (t[p].ls)
#define rs(p) (t[p].rs)

int get_new(int u, int v, int w) {
	tot++;
	t[tot].u = u, t[tot].v = v, t[tot].val = w;
	return tot;
}

void push(int p, int w) {
	t[p].tag += w;
	t[p].val += w;
}

void down(int p) {
	if (!t[p].tag) return ;
	push(ls(p), t[p].tag);
	push(rs(p), t[p].tag);
	t[p].tag = 0;
}

int merge(int u, int v) {
	if (!u || !v) return u + v;
	down(u), down(v);
	if (t[u].val > t[v].val) swap(u, v);
	rs(u) = merge(rs(u), v);
	if (t[ls(u)].dis < t[rs(u)].dis) swap(ls(u), rs(u));
	t[u].dis = t[rs(u)].dis + 1;
	return u;
}

int del(int x) {
	down(x);
	return merge(ls(x), rs(x));
}

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

void link(int u, int v, int w) {
	if (u == v) return ;
	int qwq = get_new(u, v, w);
	rt[v] = merge(rt[v], qwq);
}

int n;
int stk[N], top;
bool vis[N];
int cnt;

signed main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n;
	n++;
	int r = 1;
	for (int i = 2; i <= n; i++) {
		int sp, w;
		cin >> sp >> w;
		sp++;
		link(sp, i, w);
		for (int j = 1; j <= n; j++) {
			int w;
			cin >> w;
			link(j, i, w);
		}
	}
	for (int i = 1; i <= 2 * n; i++) fa[i] = i;
	for (int i = 1; i <= n; i++) link(i, i % n + 1, inf);
	top = 0;
	cnt = n;
	stk[++top] = r;
	vis[r] = 1;
	int ans = 0;
	while (rt[stk[top]]) {
		int id = rt[stk[top]];
		int u = find(t[id].u);
		if (u == stk[top]) {
			rt[stk[top]] = del(rt[stk[top]]);
			continue;
		}
		if (!vis[u]) {
			stk[++top] = u;
			vis[u] = 1;
			continue;
		}
		int p = ++cnt;
		while (vis[u]) {
			int v = stk[top];
			top--;
			vis[v] = 0;
			fa[v] = p;
			int ww = t[rt[v]].val;
			push(rt[v], -ww);
			if (find(t[rt[v]].v) != find(r)) ans += ww;
			rt[v] = del(rt[v]);
			rt[p] = merge(rt[p], rt[v]);
		}
		stk[++top] = p;
		vis[p] = 1;
	}
	cout << ans;
	QwQ330AwA;
}