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

#define int long long
#define double long double
#define rep(i, n) for (int i = 0; i < (n); i++)
#define reps(i, n) for (int i = 1; i <= (n); i++)
#define all(x) begin(x), end(x)
#define uniq(x) (x).erase(unique(all(x)), end(x))
#define bit(n) (1LL << (n))
#define dump(x) cerr << #x " = " << (x) << endl
using vint = vector<int>;
using vvint = vector<vint>;
using pint = pair<int, int>;
using vpint = vector<pint>;
template<typename T> using priority_queue_rev = priority_queue<T, vector<T>, greater<T>>;
constexpr double pi = 3.1415926535897932384626433832795028L;
constexpr int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};
constexpr int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
int gcd(int a, int b) {
    while (b) { swap(a %= b, b); }
    return a;
}
int lcm(int a, int b) { return a / gcd(a, b) * b; }
template<typename T> void fin(T mes) {
    cout << mes << endl;
    exit(0);
}
template<typename T, typename U> bool chmax(T &a, const U &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> bool chmin(T &a, const U &b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &rhs) {
    os << "(" << rhs.first << ", " << rhs.second << ")";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const vector<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
struct setup {
    static constexpr int PREC = 20;
    setup() {
        cout << fixed << setprecision(PREC);
        cerr << fixed << setprecision(PREC);
    };
} setup;

int N;
int a[220000], b[220000];
bool nichi[220000];
vint G[220000];
void dfs(int cur, int prev) {
    nichi[cur] = !nichi[prev];
    rep(i, G[cur].size()) {
        int next = G[cur][i];
        if (next == prev) { continue; }
        dfs(next, cur);
    }
}
void ultra() {
    vint m0, m1, m2;
    reps(i, N) {
        if (i % 3 == 0) { m0.push_back(i); }
        if (i % 3 == 1) { m1.push_back(i); }
        if (i % 3 == 2) { m2.push_back(i); }
    }
    reps(i, N) {
        if (!nichi[i]) {
            if (m1.size() > 0) {
                cout << m1.back() << endl;
                m1.pop_back();
            } else if (m2.size() > 0) {
                cout << m2.back() << endl;
                m2.pop_back();
            } else {
                cout << m0.back() << endl;
                m0.pop_back();
            }
        } else {
            cout << m0.back() << endl;
            m0.pop_back();
        }
    }
    exit(0);
}
signed main() {
    cin >> N;
    reps(i, N - 1) {
        cin >> a[i] >> b[i];
        G[a[i]].push_back(b[i]), G[b[i]].push_back(a[i]);
    }
    dfs(1, 0);
    int cnt = 0;
    reps(i, N) { cnt += nichi[i]; }
    if (cnt * 2 > N) {
        reps(i, N) { nichi[i] = !nichi[i]; }
    }
    // 0の数は1の数以上
    vint m0, m1, m2;
    reps(i, N) {
        if (i % 3 == 0) { m0.push_back(i); }
        if (i % 3 == 1) { m1.push_back(i); }
        if (i % 3 == 2) { m2.push_back(i); }
    }
    if (N * 2 <= cnt * 3) {
        ultra();
    } else {
        vint ans;
        reps(i, N) {
            if (!nichi[i]) {
                if (m1.size() > 0) {
                    ans.push_back(m1.back());
                    m1.pop_back();
                } else {
                    if (m0.size() == 0) { ultra(); }
                    ans.push_back(m0.back());
                    m0.pop_back();
                }
            } else {
                if (m2.size() > 0) {
                    ans.push_back(m2.back());
                    m2.pop_back();
                } else {
                    if (m0.size() == 0) { ultra(); }
                    ans.push_back(m0.back());
                    m0.pop_back();
                }
            }
        }
        rep(i, ans.size()) { cout << ans[i] << endl; }
    }
}


Measured memory_bytes: 23912