Submission #533863

#	Time	Username	Problem	Language	Result	Execution time	Memory
533863		Lobo	Construction of Highway (JOI18_construction)	C++17	100 / 100	1010 ms	20328 KiB

construction

#include<bits/stdc++.h>
using namespace std;

const long long inf = (long long) 1e18 + 10;
const int inf1 = (int) 1e9 + 10;
// #define int long long
#define dbl long double
#define endl '\n'
#define sc second
#define fr first
#define mp make_pair
#define pb push_back
#define all(x) x.begin(), x.end()

#define maxn 100100

int n, a[maxn], b[maxn], c[maxn], sz[maxn], pai[maxn], ant[maxn], h[maxn], bit[maxn];
vector<int> g[maxn];
vector<pair<pair<int,int>,int>> bl[maxn];

void att(int pos, int val) {
    for(int i = pos; i <= n; i+= i&-i) {
        bit[i]+= val;
    }
}

int qrr(int pos) {
    int val = 0;
    for(int i = pos; i > 0; i-= i&-i) {
        val+= bit[i];
    }
    return val;
}

void dfshld(int u) {
    pair<int,int> mx;
    for(auto v : g[u]) {
        mx = max(mx,mp(sz[v],v));
    }

    if(mx.sc == 0) return;

    pai[mx.sc] = pai[u];
    ant[mx.sc] = u;
    dfshld(mx.sc);
    for(auto v : g[u]) {
        if(v == mx.sc) continue;
        pai[v] = v;
        ant[v] = u;
        dfshld(v);
    }
}

void dfssz(int u, int ant) {
    sz[u] = 1;
    for(auto v : g[u]) {
        if(v == ant) continue;
        h[v] = h[u]+1;
        dfssz(v,u);
        sz[u]+= sz[v];
    }
}


void solve() {
    cin >> n;

    vector<int> cc;
    for(int i = 1; i <= n; i++) {
        cin >> c[i];
        c[i] = -c[i];
        cc.pb(c[i]);
    }

    sort(all(cc));
    cc.erase(unique(all(cc)),cc.end());

    for(int i = 1; i <= n; i++) {
        c[i] = upper_bound(all(cc),c[i]) - cc.begin();
    }

    for(int i = 1; i <= n-1; i++) {
        cin >> a[i] >> b[i];
        g[a[i]].pb(b[i]);
    }

    dfssz(1,1);
    ant[1] = 0;
    pai[1] = 1;
    dfshld(1);

    // for(int i = 1; i <= n; i++) {
    //     cout << i << " " << ant[i] << " " << pai[i] << endl;
    // }

    bl[1].pb(mp(mp(0,0),c[1]));
    //mp(mp(altura minima,altura maxima),cor)

    for(int i = 1; i <= n-1; i++) {
        int u = a[i];

        vector<pair<pair<int,int>,int>> cols;
        int v = u;
        while(v != 0) {
            // cout << "- " << v << endl;
            if(pai[v] != v) {
                for(auto x : bl[pai[v]]) {
                    if(x.fr.fr <= h[v]) cols.pb(mp(mp(x.fr.fr,min(h[v],x.fr.sc)),x.sc));
                }
            }
            else {
                cols.pb(mp(mp(h[v],h[v]),bl[v].back().sc));
            }

            v = ant[pai[v]];
        }

        // cout << b[i] << " " << c[b[i]] << endl;
        sort(all(cols));
        int ans = 0;
        for(auto X : cols) {
            int qtd = X.fr.sc-X.fr.fr+1;
            int col = X.sc;
            // cout << " " << X.fr.fr << " " << X.fr.sc << " " << col << endl;

            ans+= qtd*qrr(col-1);
            att(col,qtd);
        }


        cout << ans << endl;

        int ant1 = 0;
        for(auto X : cols) {
            int qtd = X.fr.sc-X.fr.fr+1;
            int col = X.sc;
            att(col,-qtd);
        }

        //atualizacao
        //bl[i] tem que estar em ordem decrescente, com o bloco do pai sendo o ultimo

        v = b[i];
        int newc = c[b[i]];
        while(v != 0) {
            // cout << "   " << v << endl;
            while(bl[pai[v]].size() && bl[pai[v]].back().fr.sc <= h[v]) bl[pai[v]].pop_back();
            if(bl[pai[v]].size() != 0) {
                auto x = bl[pai[v]].back();
                // cout << "    " << x.fr.fr << " " << x.fr.sc << " " << x.sc << " " << h[v] << endl;
                bl[pai[v]].pop_back();
                bl[pai[v]].pb(mp(mp(h[v]+1,x.fr.sc),x.sc));
            }

            
            bl[pai[v]].pb(mp(mp(h[pai[v]],h[v]),newc));
            
            v = ant[pai[v]];
        }


    }


}

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(0);

    // freopen("in.in", "r", stdin);
    //freopen("out.out", "w", stdout);

    int tt = 1;
    // cin >> tt;
    while(tt--) solve();

}

Compilation message (stderr)

construction.cpp: In function 'void solve()':
construction.cpp:133:13: warning: unused variable 'ant1' [-Wunused-variable]
  133 |         int ant1 = 0;
      |             ^~~~

• Subtask 1: 7 / 7
• Subtask 2: 9 / 9
• Subtask 3: 84 / 84