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

struct iofast_t {
    iofast_t() {
        ios::sync_with_stdio(false);
        cin.tie(nullptr); cout.tie(nullptr);
    }
} iofast;

struct uns_t {} uns;
template <typename Element, typename Head, typename ...Args>
auto vec(Element init, Head arg, Args ...args) {
    if constexpr (sizeof...(Args) == 0) return std::vector(arg, init);
    else return std::vector(arg, vec(init, args...));
}
template <typename Element, typename Head, typename ...Args>
auto vec(uns_t, Head arg, Args ...args) {
    return vec(Element(), arg, args...);
}

template <typename T, typename Compare = less<T>>
T &chmin(T &l, T r, Compare &&f = less<T>()) { return l = min(l, r, f); }
template <typename T, typename Compare = less<T>>
T &chmax(T &l, T r, Compare &&f = less<T>()) { return l = max(l, r, f); }

int main() {
    int n; cin >> n;

    auto g = vec<int>(uns, n, 0);
    for (int i = 1; i < n; ++i) {
        int a, b; cin >> a >> b; --a; --b;
        g[a].push_back(b);
        g[b].push_back(a);
    }

    int root = 0;
    auto leaf = vec<int>(uns, 0);
    for (int i = 0; i < n; ++i) {
        if (size(g[i]) == 1) {
            leaf.push_back(i);
        }
        if (size(g[i]) != 1) {
            root = i;
        }
    }

    if (size(leaf) == 2) {
        cout << "Yes" << endl;
        return 0;
    }

    auto dist = vec<int>(-1, n);
    queue<int> que;

    dist[root] = 0;
    que.push(root);
    while (!que.empty()) {
        int c = que.front(); que.pop();
        for (auto v : g[c]) {
            if (dist[v] != -1) continue;
            dist[v] = dist[c] + 1;
            que.push(v);
        }
    }

    bool ans = true;

    int p = dist[leaf[0]];
    for (auto i : leaf) {
        ans &= p == dist[i];
    }

    cout << (ans ? "Yes" : "No") << endl;
}