#include <bits/stdc++.h>
#define pb emplace_back
using namespace std;
typedef long long ll;
const int maxn = 1e3 + 5;
int n;
vector<int> g[maxn];
ll ans = 0;
void dfs(int u,int fa,int dep) {
    ans += dep >> 1;
    for(auto v : g[u]) {
        if(v == fa)continue ;
        dfs(v , u , dep + 1);
    }
    return ;
}
int main() {
    freopen("Sergeyas.in","r",stdin);
    freopen("Sergeyas.out","w",stdout);
    scanf("%d",&n);
    if(n > maxn)return 0;
    for(int i = 1;i < n;++ i) {
        int u,v;
        scanf("%d%d",&u,&v);
        g[u].pb(v);
        g[v].pb(u);
    }
    for(int i = 1;i <= n;++ i)dfs(i , 0 , 1);
    printf("%lld",ans / 2);
    fclose(stdin);
    fclose(stdout);
    return 0;
}