Submission #1097739

#	Time	Username	Problem	Language	Result	Execution time	Memory
1097739		Neco_arc	Synchronization (JOI13_synchronization)	C++17	100 / 100	145 ms	20208 KiB

synchronization

#include <bits/stdc++.h>

#define ll long long
#define ull unsigned long long
#define all(x) x.begin(), x.end()
#define Neco "Synchronization"
#define resp(x) sort(all(x)), x.resize(unique(all(x)) - x.begin())
#define getbit(x,i) ((x >> i)&1)
#define _left id * 2, l, mid
#define _right id * 2 + 1, mid + 1, r
#define cntbit(x) __builtin_popcountll(x)
#define fi(i, a, b) for(int i = a; i <= b; i++)
#define fid(i, a, b) for(int i = a; i >= b; i--)
#define maxn (int) 2e5 + 7

using namespace std;

const ll mod = 1e9 + 7; //972663749
const ll base = 911382323;

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll GetRandom(ll l, ll r) {
    return uniform_int_distribution<ll> (l, r)(rng);
}

int n, m, q;
int cl[maxn], ans[maxn], last[maxn];
int p[maxn], In[maxn], Out[maxn];
pair<int, int> E[maxn];
vector<int> edges[maxn];

void pre_dfs(int u, int par) {
    static int Time = 0;
    In[u] = ++Time, p[Time] = u;
    for(int v : edges[u]) if(v != par) {
        pre_dfs(v, u);
    }
    Out[u] = Time;
}

struct IT {
    int st[4 * maxn];

    void update(int x, int val, int id = 1, int l = 1, int r = n) {
        if(l > x || r < x) return;
        if(l == r) return st[id] = val, void();

        int mid = (l + r) >> 1;
        update(x, val, _left), update(x, val, _right);
        st[id] = max(st[id * 2], st[id * 2 + 1]);
    }

    int get(int x, int val, int id = 1, int l = 1, int r = n) {
        if(l > x || st[id] < val) return -1;
        if(l == r) return p[l];

        int mid = (l + r) >> 1;
        int w = get(x, val, _right);
        if(w == -1) w = get(x, val, _left);

        return w;
    }

} St;

void solve()
{
    cin >> n >> m >> q;
    fi(i, 1, n - 1) {
        int x, y; cin >> x >> y;
        E[i] = {x, y};
        edges[x].push_back(y), edges[y].push_back(x);
    }

    pre_dfs(1, 0);
    fi(i, 1, n) {
        St.update(In[i], Out[i]);
        ans[i] = 1;
    }

    fi(i, 1, m) {
        int id, u, v; cin >> id;
        tie(u, v) = E[id]; if(In[u] > In[v]) swap(u, v);
        int p = St.get(In[u], Out[u]);

        if(!cl[id]) {
            ans[p] += ans[v] - last[v];
            St.update(In[v], 0);
        }
        else {
            last[v] = ans[v] = ans[p];
            St.update(In[v], Out[v]);
        }

        cl[id] ^= 1;
    }

    fi(i, 1, q) {
        int x; cin >> x;
        cout << ans[St.get(In[x], Out[x])] << '\n';
    }


}


int main()
{

    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    if(fopen(Neco".inp", "r")) {
        freopen(Neco".inp", "r", stdin);
        freopen(Neco".out", "w", stdout);
    }

    int nTest = 1;
//    cin >> nTest;

    while(nTest--)
    {
        solve();
    }


    return 0;
}

Compilation message (stderr)

synchronization.cpp: In function 'int main()':
synchronization.cpp:115:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  115 |         freopen(Neco".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
synchronization.cpp:116:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  116 |         freopen(Neco".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 10 / 10
• Subtask 4: 20 / 20
• Subtask 5: 40 / 40