Submission #1185948

#	Time	Username	Problem	Language	Result	Execution time	Memory
1185948		icebear	Klasika (COCI20_klasika)	C++20	110 / 110	1735 ms	123888 KiB

klasika

// ~~ icebear love attttt ~~
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> ii;
typedef pair<int, ii> iii;

template<class T>
    bool minimize(T &a, const T &b) {
        if (a > b) return a = b, true;
        return false;
    }

template<class T>
    bool maximize(T &a, const T &b) {
        if (a < b) return a = b, true;
        return false;
    }

#define FOR(i,a,b) for(int i=(a); i<=(b); ++i)
#define FORR(i,a,b) for(int i=(a); i>=(b); --i)
#define REP(i, n) for(int i=0; i<(n); ++i)
#define RED(i, n) for(int i=(n)-1; i>=0; --i)
#define MASK(i) (1LL << (i))
#define BIT(S, i) (((S) >> (i)) & 1)
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define task "icebearat"

const int MOD = 1e9 + 7;
const int inf = 1e9 + 27092008;
const ll INF = 1e18 + 27092008;
const int N = 2e5 + 5;
const int BLOCK_SIZE = 2709;
int q, n;
vector<ii> G[N];
int f[N], tin[N], tout[N], tour[N], timer = -1;

struct Query {
    int type, u, v;
} Q[N];

struct Trie {
    struct Node {
        Node *child[2];
        bool exist;

        Node() {
            child[0] = child[1] = NULL;
        }
    };

    Node *root;
    Trie() {
        root = new Node();
    }

    void add(int x) {
        Node *p = root;
        RED(j, 31) {
            int pos = BIT(x, j);
            if (p -> child[pos] == NULL) p -> child[pos] = new Node();
            p = p -> child[pos];
        }
    }

    int maxXor(int x) {
        Node *p = root;
        int ans = 0;
        RED(j, 31) {
            int pos = BIT(x, j);
            if (p -> child[pos ^ 1] != NULL) {
                ans |= MASK(j);
                p = p -> child[pos ^ 1];
            }
            else {
                if (p -> child[pos] == NULL) return 0;
                p = p -> child[pos];
            }
        }
        return ans;
    }
} trie[N / BLOCK_SIZE];

void dfs(int u, int par) {
    tin[u] = ++timer;
    tour[timer] = u;
    for(ii x : G[u]) {
        int v, w; tie(v, w) = x;
        if (v == par) continue;
        f[v] = f[u] ^ w;
        dfs(v, u);
    }
    tout[u] = timer;
}

void init(void) {
    cin >> q;
    string type;
    n = 1;
    FOR(i, 1, q) {
        cin >> type >> Q[i].u >> Q[i].v;
        if (type == "Add") {
            n++;
            Q[i].type = 1;
            G[Q[i].u].pb(mp(n, Q[i].v));
        } else Q[i].type = 2;
    }

    dfs(1, -1);
}

void process(void) {
    int node = 1;
    trie[0].add(0);
    FOR(i, 1, q) {
        if (Q[i].type == 1) {
            node++;
            int pos = tin[node];
            trie[pos / BLOCK_SIZE].add(f[node]);
        } else {
            int ans = 0;
            int a = Q[i].u;
            int l = tin[Q[i].v], r = tout[Q[i].v];
            int blockL = (l + BLOCK_SIZE - 1) / BLOCK_SIZE;
            int blockR = r / BLOCK_SIZE;

            if (blockL >= blockR) {
                FOR(j, l, r) {
                    int b = tour[j];
                    if (b <= node) maximize(ans, f[a] ^ f[b]);
                }
                cout << ans << '\n';
                continue;
            }

            FOR(j, l, blockL * BLOCK_SIZE - 1) {
                int b = tour[j];
                if (0 < b && b <= node) maximize(ans, f[a] ^ f[b]);
            }
            FOR(j, blockR * BLOCK_SIZE, r) {
                int b = tour[j];
                if (0 < b && b <= node) maximize(ans, f[a] ^ f[b]);
            }
            FOR(j, blockL, blockR - 1) maximize(ans, trie[j].maxXor(f[a]));

            cout << ans << '\n';
        }
    }
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    int tc = 1;
//    cin >> tc;
    while(tc--) {
        init();
        process();
    }
    return 0;
}

Compilation message (stderr)

klasika.cpp: In function 'int main()':
klasika.cpp:160:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  160 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
klasika.cpp:161:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  161 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 11 / 11
• Subtask 2: 22 / 22
• Subtask 3: 33 / 33
• Subtask 4: 44 / 44