#include <bits/stdc++.h>
#include <sstream>
#include <fstream>
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//WAS CREAtED BY BAISYN MUKHAMMED//
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#define et "\n"
#define ll long long
#define ff first
#define ss second
#define pb push_back
#define ioi ios::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
#define M 1000000007
using namespace std;
ll n,m,a[211111];
void solve() {
cin >> n;
for (int i = 1;i < n;i++) {
ll x,y,z;
cin >> x >> y >> z;
m += z;
}
ll q;
cin >> q;
ll a,b,c,g,e;
cin >> a >> b >> c >> g >> e;
cout << m << et;
}
int main () {
ioi;
// freopen("input.txt","r",stdin);
// freopen("output.txt","w",stdout);
ll t = 1;
// cin >> t;
while (t--) {
solve();
}
}
