Submission #195626

#	Time	Username	Problem	Language	Result	Execution time	Memory
195626		karma	Ball Machine (BOI13_ballmachine)	C++14	100 / 100	322 ms	32108 KiB

ballmachine

#include <bits/stdc++.h>
#define pb          emplace_back
#define ll          long long
#define fi          first
#define se          second
#define mp          make_pair
//#define int         int64_t

using namespace std;

const int N = (int)1e5 + 2;
const int logN = 20;

typedef pair<int, int> pii;
int p[N][logN + 1], del[N], d[N], deg[N];
int Min[N], order[N], cur = 0;
int root, n, q, x, k, low, high, mid;
vector<int> a[N];
set<pii> leaf;

void DFS(int u) {
    deg[u] = a[u].size(), Min[u] = u;
    for(int i = 1; i <= logN; ++i) p[u][i] = p[p[u][i - 1]][i - 1];
    for(int v: a[u]) {
        d[v] = d[u] + 1, DFS(v);
        Min[u] = min(Min[u], Min[v]);
    }
}

void Order(int u) {
    vector<pii> child;
    for(int v: a[u]) child.pb(Min[v], v);
    sort(child.begin(), child.end());
    for(pii p: child) Order(p.se);
    order[u] = ++cur;
    if(deg[u] == 0) leaf.insert(mp(order[u], u));
}

int Node(int x, int step) {
    for(int i = logN; i >= 0; --i)
        if(step >= (1 << i)) x = p[x][i], step -= (1 << i);
    return x;
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    #define Task        "test"
    if(fopen(Task".inp", "r")) {
        freopen(Task".inp", "r", stdin);
        freopen(Task".out", "w", stdout);
    }
    cin >> n >> q;
    for(int i = 1; i <= n; ++i) {
        cin >> p[i][0]; a[p[i][0]].pb(i);
        if(!p[i][0]) root = i;
    }
    DFS(root); Order(root);
    while(q --) {
        cin >> x >> k;
        if(x == 1) {
            while(k --) {
                x = (*leaf.begin()).se; leaf.erase(leaf.begin());
                if(--deg[p[x][0]] == 0) leaf.insert(mp(order[p[x][0]], p[x][0]));
                del[x] = 1;
            }
            cout << x << '\n';
        } else {
            x = k;
            for(int i = logN; i >= 0; --i) {
                if(del[p[x][i]]) x = p[x][i];
            }
            del[x] = 0, leaf.insert(mp(order[x], x));
            if(++deg[p[x][0]] == 1) leaf.erase(mp(order[p[x][0]], p[x][0]));
            cout << d[k] - d[x] << '\n';
        }
    }
}

Compilation message (stderr)

ballmachine.cpp: In function 'int32_t main()':
ballmachine.cpp:50:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".inp", "r", stdin);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
ballmachine.cpp:51:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".out", "w", stdout);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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