#include <iostream>


using namespace std;





const int maxn = 1000;


int n;


int fa[maxn], cnt[maxn];





int getRoot(int v) {


    if (fa[v] == v) return v;


    return getRoot(fa[v]);


}





int main() {


    cin >> n;


    for (int i = 0; i < n; ++i) {


        fa[i] = i;


        cnt[i] = 1;


    }


    int ans = 0;


    for (int i = 0; i < n - 1; ++i) {


        int a, b, x, y;


        cin >> a >> b;


        x = getRoot(a);


        y = getRoot(b);


        ans += cnt[x] * cnt[y];


        fa[x] = y;


        cnt[y] += cnt[x];


    }


    cout << ans << endl;


    return 0;


}

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