Submission #587895

#	Time	Username	Problem	Language	Result	Execution time	Memory
587895		MohamedAliSaidane	Ball Machine (BOI13_ballmachine)	C++14	100 / 100	913 ms	27848 KiB

ballmachine

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

        using namespace __gnu_pbds;
        using namespace std;

        typedef tree<int,null_type,less<int>,rb_tree_tag,
        tree_order_statistics_node_update> indexed_set;

        typedef long long ll;
        typedef long double ld;

        ///#define int ll

        typedef pair<int,int> pii;
        typedef pair<ll,ll> pll;
        typedef pair<ld,ld> pld;

        typedef vector<int> vi;
        typedef vector<ll> vll;
        typedef vector<pii> vpi;
        typedef vector<pll> vpl;

        #define pb push_back
        #define popb pop_back
        #define pp pop_back
        #define pf push_front
        #define popf pop_front
        #define all(x) (x).begin(),(x).end()
        #define ff first
        #define ss second



        int nx[4] = {0,0,1,-1}, ny[4] = {1,-1,0,0};
        ll gcd(ll a , ll b) {return b ? gcd(b , a % b) : a ;}
        ll lcm(ll a , ll b) {return (a * b) / gcd(a , b);}


        const ll MOD =   998244353;
        const int nax = 1e5 + 4;
        int n, q;
        vi adj[nax];
        int sp[nax][20], d[nax], mini[nax];
        int root = 1;
        void dfs(int x, int p)
        {
            d[x] = d[p]  + 1;
            sp[x][0] = p;
            mini[x] = x;
            for(auto e: adj[x])
            {
                if(e != p)
                {
                    dfs(e,x);
                    mini[x] = min(mini[x], mini[e]);
                }
            }
        }
        void build()
        {
            for(int j= 1; j < 20; j ++)
                for(int i= 1 ; i <= n ;i ++)
                    sp[i][j] = sp[sp[i][j - 1]][j - 1];

        }
        int jump(int a, int k)
        {
            for(int i = 0; i < 20; i ++)
                if((1 << i) & k)
                    a = sp[a][i];
            return a;
        }
        int lca(int a, int b)
        {
            if(d[a] < d[b])
                swap(a,b);
            a = jump(a, d[a] - d[b]);
            if(a == b)
                return a;
            for(int i = 19 ; i >= 0; i--)
                if(sp[a][i] != sp[b][i])
                    a = sp[a][i], b = sp[b][i];
            return sp[a][0];
        }
        bool comp(int a, int b)
        {
            int c = lca(a,b);
            if(c == a)
                return false;
            else if(c == b)
                return true;
            int d1 = d[a] - d[c] - 1;
            int d2 = d[b] - d[c] - 1;
            int p1 = jump(a,d1);
            int p2 = jump(b,d2);
            if(mini[p1] < mini[p2])
                return true;
            else
                return false;
        }
        void solve()
        {
            cin >> n >> q;
            for(int i=  1; i <= n ;i ++)
            {
                int x; cin >> x;
                if(x == 0)
                    root = i;
                else
                {
                    adj[x].pb(i);
                    adj[i].pb(x);
                }
            }
            d[0] = -1;
            dfs(root,0);
            build();
            vi nodes;
            for(int i= 1; i <= n ;i ++)
                nodes.pb(i);
            sort(all(nodes),comp);
            set<int> s;
            for(int i = 0; i < n; i ++)
                s.insert(i);
            int cor[n + 1];
            for(int i = 0; i < n ; i ++)
                cor[nodes[i]] = i;
            while(q--)
            {
                int type;
                cin >> type;
                if(type == 1)
                {
                    int k; cin >> k;
                    for(int i = 1;i < k; i ++)
                        s.erase(s.begin());
                    int idx = *(s.begin());
                    cout << nodes[idx] << '\n';
                    s.erase(s.begin());
                }
                else
                {
                    int x; cin >> x;
                    int debut = 1;
                    int fin = d[x];
                    int rep = 0;
                    while(debut <= fin)
                    {
                        int mid = (debut + fin)/2;
                        if(s.count(cor[jump(x,mid)]) == 0)
                        {
                            rep = mid;
                            debut=  mid + 1;
                        }
                        else
                            fin = mid - 1;
                    }
                    s.insert(cor[jump(x,rep)]);
                    cout << rep << '\n';
                }
            }
        }

        int32_t main()
        {
            ios::sync_with_stdio(false);
            cin.tie(0); cout.tie(0);
            int tt = 1; //cin >> tt;
            while(tt --)
                solve();
        }

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