Submission #1123166

#	Time	Username	Problem	Language	Result	Execution time	Memory
1123166		JanPham	Ball Machine (BOI13_ballmachine)	C++17	100 / 100	456 ms	31080 KiB

ballmachine

#include <bits/stdc++.h>
 
using namespace std;
 
#define pb push_back
#define fi first
#define se second
#define TranLeThanhTam "TranLeThanhTam"
#define all(v) v.begin(),v.end()
#define reset(a,i) memset(a,i,sizeof(a))
#define FOR(i,a,b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i,a,b) for (int i = (a), _b = (b); i >= _b; --i)
#define compact(v) sort(all(v)), v.erase(unique(all(v)), end(v))
#define sz(v) (int) v.size()
#define MASK(i) (1 << (i))
 
typedef long long ll;
typedef long double lb;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
 
const int Thanh_Tam = 1e5 + 17;
const int inf = 1e9 + 17;
const long long infll = 1e18 + 17;
const int MOD = 1e9 + 7;
const int Log = 18;
const int dx[4] = {-1, 0, 0, 1};
const int dy[4] = {0, -1, 1, 0};
const int max_block_size = 270;
const ll P = 311;
const int maxA = 1e2 + 17;
const int addi = 1e9;
const char dir[4] = {'W', 'S', 'N', 'E'};
const int Mod[3] = {998244353, MOD, 759186269};
 
ll mul(ll a, ll b, ll mod);
ll binpow(ll a, ll b, ll mod)
{
    ll res = 1;
    while (b > 0)
    {
        if (b & 1) res = mul(res,a,mod);
        b >>= 1;
        a = mul(a,a,mod);
    }
    return res;
}
ll add(ll a, ll b, ll mod) { return (a + b) % mod;                 }
ll sub(ll a, ll b, ll mod) { return (a - b + mod) % mod;          }
ll mul(ll a, ll b, ll mod) { return ((a % mod) * (b % mod)) % mod; }
ll div(ll a, ll b, ll mod) { return mul(a, binpow(b, mod - 2, mod), mod); }
 
mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());
ll rand_range(ll l, ll r) { return uniform_int_distribution<ll>(l,r)(rng); }
 
struct Segment
{
    vector<int> st;
    vector<int> lz;

    Segment() {}

    Segment(int n)
    {
        int _n = 1;
        while (_n < n) _n <<= 1;
        st.assign((_n << 1) + 1, 0);
        lz.assign((_n << 1) + 1, false);
        return;
    }

    void down(int id, int l, int r)
    {
        if (!lz[id]) return;
        
        if (lz[id] == 1)
        {
            int mid = (l + r) >> 1;
            st[id << 1] = (mid - l + 1);
            st[(id << 1) | 1] = (r - mid);
            lz[id << 1] = lz[(id << 1) | 1] = 1;
        }
        else
        {
            int mid = (l + r) >> 1;
            st[id << 1] = 0;
            st[(id << 1) | 1] = 0;
            lz[id << 1] = lz[(id << 1) | 1] = 2;
        }

        lz[id] = 0;
        return;
    }

    void update(int id, int l, int r, int u, int v)
    {
        if (v < l || r < u) return;
        if (u <= l && r <= v)
        {
            st[id] = (r - l + 1);
            lz[id] = 1;
            return;
        } 

        down(id, l, r);
        int mid = (l + r) >> 1;
        update(id << 1, l, mid, u, v);
        update((id << 1) | 1, mid + 1, r, u, v);
        st[id] = st[id << 1] + st[(id << 1) | 1];
        return;
    }

    void update2(int id, int l, int r, int u, int v)
    {
        if (v < l || r < u) return;
        if (u <= l && r <= v)
        {
            st[id] = 0;
            lz[id] = 2;
            return;
        } 

        down(id, l, r);
        int mid = (l + r) >> 1;
        update2(id << 1, l, mid, u, v);
        update2((id << 1) | 1, mid + 1, r, u, v);
        st[id] = st[id << 1] + st[(id << 1) | 1];
        return;
    }

    int query(int id, int l, int r, int u, int v)
    {
        if (v < l || r < u) return 0;
        if (u <= l && r <= v) return st[id];

        down(id, l, r);
        int mid = (l + r) >> 1;
        return query(id << 1, l, mid, u, v) + query((id << 1) | 1, mid + 1, r, u, v);
    }
} tree;

int n, q, root, timer = 0;
vector<int> adj[Thanh_Tam];
int tour[Thanh_Tam], f[Thanh_Tam], tin[Thanh_Tam];
int par[Thanh_Tam][Log + 1], h[Thanh_Tam];
 
void dfs3(int u, int Par)
{
    f[u] = u;
    for (int v : adj[u])
    {
        if (v == Par) continue;
        dfs3(v, u);
        f[u] = min(f[u], f[v]);
    }

    return;
}

void dfs1(int u, int Par)
{   
    vector<pii> value;
    for (int v : adj[u])
    {
        if (v == Par) continue;
        value.pb({f[v], v});
    }

    sort(all(value));
    for (pii T : value) dfs1(T.se, u);
    tour[++timer] = u;
    tin[u] = timer;

    return;
}
 
void dfs2(int u, int Par)
{
    for (int v : adj[u])
    {
        if (v == Par) continue;
        h[v] = h[u] + 1;
        par[v][0] = u;
        dfs2(v, u);
    }
    return;
}

int walk(int u, int dis)
{
    int v = u;
    FORD(j, Log, 0)
        if (dis >= MASK(j))
        {
            dis -= MASK(j);
            v = par[v][j];
        }
    return v;
}

void prepare()
{
    timer = 0;
    dfs3(root, -1);
    dfs1(root, -1);
    dfs2(root, -1);
    tree = Segment(n);
 
    par[root][0] = 0;
    FOR(j,1,Log)
        FOR(i,1,n)
            par[i][j] = par[par[i][j - 1]][j - 1];
    return;
}
 
void ThanhTam()
{
    cin >> n >> q;
    FOR(v,1,n)
    {
        int u;
        cin >> u;
        if (u == 0)
        {
            root = v;
            continue;
        }
        adj[u].pb(v);
        adj[v].pb(u);
    }
 
    prepare();
    while (q--)
    {
        int type, x;
        cin >> type >> x;
        if (type == 1)
        {
            int l = 1, r = n, pos = 0;
            while (l <= r)
            {
                int mid = (l + r) >> 1;
                if (mid - tree.query(1, 1, n, 1, mid) < x)
                {
                    pos = mid;
                    l = mid + 1;
                }
                else r = mid - 1;
            }
            cout << tour[pos + 1] << '\n';
            tree.update(1, 1, n, 1, pos + 1);
        }
        else
        {
            int l = 0, r = h[x], ans = 0;
            while (l <= r)
            {
                int mid = (l + r) >> 1, acs = walk(x, mid);
                if (tree.query(1, 1, n, tin[acs], tin[acs]) == 1)
                {
                    ans = mid;
                    l = mid + 1;
                }
                else r = mid - 1;
            }
            int acs = walk(x, ans);
            cout << ans << '\n';
            tree.update2(1, 1, n, tin[acs], tin[acs]);
        }
    }
    return;
}
 
signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
 
    if (fopen(TranLeThanhTam".inp","r"))
    {
        freopen(TranLeThanhTam".inp","r",stdin);
        freopen(TranLeThanhTam".out","w",stdout);
    }
 
    int t = 1;
    //cin >> t;
    while (t--)
        ThanhTam();
 
    return 0;
}

Compilation message (stderr)

ballmachine.cpp: In function 'int main()':
ballmachine.cpp:282:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  282 |         freopen(TranLeThanhTam".inp","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ballmachine.cpp:283:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  283 |         freopen(TranLeThanhTam".out","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 25 / 25
• Subtask 2: 30 / 30
• Subtask 3: 40 / 40
• Subtask 4: 5 / 5