Submission #527322

#	Time	Username	Problem	Language	Result	Execution time	Memory
527322		jalsol	Birthday gift (IZhO18_treearray)	C++11	30 / 100	4018 ms	16536 KiB

treearray

#include <bits/stdc++.h>

using namespace std;

#define Task ""

struct __Init__ {
    __Init__() {
        cin.tie(nullptr)->sync_with_stdio(false);
        if (fopen(Task".inp", "r")) {
            freopen(Task".inp", "r", stdin);
            freopen(Task".out", "w", stdout); }
    }
} __init__;

using ll = long long;

#ifdef LOCAL
#define debug(x) cerr << "[" #x " = " << x << "]\n";
#else
#define debug(...)
#endif // LOCAL

#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define fi first
#define se second

#define For(i, l, r) for (int i = (l); i <= (r); ++i)
#define Ford(i, r, l) for (int i = (r); i >= (l); --i)
#define Rep(i, n) For (i, 0, (n) - 1)
#define Repd(i, n) Ford (i, (n) - 1, 0)

template<class C> int isz(const C& c) { return c.size(); }
template<class T> bool chmin(T& a, const T& b) { if (a > b) { a = b; return true; } return false; }
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } return false; }

constexpr int eps = 1e-9;
constexpr int inf = 1e9;
constexpr ll linf = 1e18;

// =============================================================================

constexpr int maxN = 2000 + 5;
constexpr int logN = 20;

int n, m, nq;
vector<int> g[maxN];
int a[maxN];

int par[maxN][logN];
int dep[maxN];

int lca[maxN][maxN];

void Dfs(int u) {
    for (int v : g[u]) if (v != par[u][0]) {
        par[v][0] = u;
        dep[v] = dep[u] + 1;
        Dfs(v);
    }
}

int getLca(int u, int v) {
    if (dep[u] < dep[v]) swap(u, v);

    Repd (i, logN) if ((dep[u] - dep[v]) >> i & 1) {
        u = par[u][i];
    }

    if (u == v) return u;

    Repd (i, logN) if (par[u][i] != par[v][i]) {
        u = par[u][i];
        v = par[v][i];
    }

    return par[u][0];
}

signed main() {
    cin >> n >> m >> nq;

    Rep (_, n - 1) {
        int u, v; cin >> u >> v;
        g[u].push_back(v);
        g[v].push_back(u);
    }

    For (i, 1, m) cin >> a[i];

    Dfs(1);

    For (j, 1, logN - 1) {
        For (i, 1, n) {
            par[i][j] = par[par[i][j - 1]][j - 1];
        }
    }

    For (i, 1, n) {
        For (j, i, n) {
            lca[i][j] = lca[j][i] = getLca(i, j);
        }
    }

    Rep (_, nq) {
        int op; cin >> op;

        if (op == 1) {
            int p, x; cin >> p >> x;
            a[p] = x;
        } else {
            int l, r, v; cin >> l >> r >> v;

            int ansL = -1, ansR = -1;

            For (i, l, r) {
                int node = a[i];

                For (j, i, r) {
                    node = lca[node][a[j]];

                    if (node == v) {
                        ansL = i;
                        ansR = j;
                        break;
                    }
                }

                if (ansL != -1) break;
            }

            cout << ansL << ' ' << ansR << '\n';
        }
    }
}

/*

*/

Compilation message (stderr)

treearray.cpp: In constructor '__Init__::__Init__()':
treearray.cpp:11:20: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 |             freopen(Task".inp", "r", stdin);
      |             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
treearray.cpp:12:20: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |             freopen(Task".out", "w", stdout); }
      |             ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 0 / 26
• Subtask 4: 0 / 44