Submission #1102411

#	Time	Username	Problem	Language	Result	Execution time	Memory
1102411		ro9669	Nile (IOI24_nile)	C++17	100 / 100	96 ms	20852 KiB

nile

#include <bits/stdc++.h>
#define fi first
#define se second
#define all(v) v.begin() , v.end()
#define sz(v) int(v.size())
#define unq(v) sort(all(v)); v.resize(unique(all(v)) - v.begin());
//#include "nile.h"
using namespace std;

typedef long long ll;
typedef pair<int , int> ii;
typedef pair<long long , int> lli;

const int maxN = int(2e5)+7;
const int inf = int(1e9)+7;

int n , q;
ll dp[maxN];
vector<int> w , a , b , e , id;
vector<ll> res;

namespace sub1{
    bool check(){
        return (q <= 5 && n <= 2000);
    }

    void solve(){
        for (int d : e){
            dp[0] = 0;
            for (int i = 0 ; i < n ; i++){
                ll s = 0;
                int x = INT_MAX;
                dp[i + 1] = ll(1e18);
                for (int j = i ; j >= 0 ; j--){
                    s += b[id[j]];
                    x = min(x , a[id[j]] - b[id[j]]);
                    if (w[id[i]] - w[id[j]] <= d){
                        if ((i - j)&1){
                            dp[i + 1] = min(dp[i + 1] , dp[j] + s);
                        }
                        else{
                            dp[i + 1] = min(dp[i + 1] , dp[j] + s + 1ll * x);
                        }
                    }
                    else{
                        break;
                    }
                }
            }
            res.push_back(dp[n]);
        }
    }
}

namespace sub2{
    bool check(){
        return (q <= 5);
    }

    void solve(){
        for (int d : e){
            dp[0] = 0;
            for (int i = 0 ; i < n ; i++){
                dp[i + 1] = dp[i] + 1ll * a[id[i]];
                if (i - 1 >= 0 && w[id[i]] - w[id[i - 1]] <= d){
                    dp[i + 1] = min(dp[i + 1] , dp[i - 1] + 1ll * b[id[i]] + 1ll * b[id[i - 1]]);
                }
                if (i - 2 >= 0 && w[id[i]] - w[id[i - 2]] <= d){
                    dp[i + 1] = min(dp[i + 1] , dp[i - 2] + 1ll * b[id[i]] + 1ll * a[id[i - 1]] + 1ll * b[id[i - 2]]);
                }
            }
            res.push_back(dp[n]);
        }
    }
}

namespace sub3{
    int fa[maxN] , p[maxN];
    ll C[maxN] , S[maxN] , X[maxN][2] , Y[maxN] , cur_ans = 0;
    vector<pair<int , ii>> event;
    vector<ii> query;

    int root(int x){
        if (fa[x] < 0) return x; else return fa[x] = root(fa[x]);
    }

    void modify(int u){
        if ((-fa[u]) % 2 == 0){
            C[u] = S[u];
        }
        else{
            C[u] = S[u] + min(X[u][0] , Y[u]);
        }
    }

    void unite(int u , int v , ll w){
        u = root(u);
        v = root(v);
        if (u == v){
            Y[u] = min(Y[u] , w);
            cur_ans -= C[u];
            modify(u);
            cur_ans += C[u];
            return;
        }
        if (-fa[u] < -fa[v]) swap(u , v);
        ll tmp[2];
        if (p[u] < p[v]){
            if ((-fa[u]) % 2 == 0){
                tmp[0] = min(X[u][0] , X[v][0]);
                tmp[1] = min(X[u][1] , X[v][1]);
            }
            else{
                tmp[0] = min(X[u][0] , X[v][1]);
                tmp[1] = min(X[u][1] , X[v][0]);
            }
        }
        else{
            swap(u , v);
            if ((-fa[u]) % 2 == 0){
                tmp[0] = min(X[u][0] , X[v][0]);
                tmp[1] = min(X[u][1] , X[v][1]);
            }
            else{
                tmp[0] = min(X[u][0] , X[v][1]);
                tmp[1] = min(X[u][1] , X[v][0]);
            }
            swap(u , v);
        }
        X[u][0] = tmp[0];
        X[u][1] = tmp[1];
        p[u] = min(p[u] , p[v]);
        C[u] += C[v];
        S[u] += S[v];
        Y[u] = min({Y[u] , Y[v] , w});
        fa[u] += fa[v];
        fa[v] = u;
        cur_ans -= C[u];
        modify(u);
        cur_ans += C[u];
    }

    void solve(){
        for (int i = 0 ; i < n ; i++){
            cur_ans += 1ll * a[id[i]];
            fa[i] = -1;
            C[i] = a[id[i]];
            S[i] = b[id[i]];
            X[i][0] = a[id[i]] - b[id[i]];
            X[i][1] = Y[i] = inf;
            p[i] = i;
        }
        for (int i = 0 ; i < n - 1 ; i++){
            event.push_back({w[id[i + 1]] - w[id[i]] , {i , i + 1}});
        }
        for (int i = 0 ; i < n - 2 ; i++){
            event.push_back({w[id[i + 2]] - w[id[i]] , {i , i + 2}});
        }
        res.resize(q);
        for (int i = 0 ; i < q ; i++){
            query.push_back({e[i] , i});
        }
        sort(all(query));
        sort(all(event));
        for (int i = 0 , j = -1 ; i < q ; i++){
            while (j + 1 < sz(event) && event[j + 1].fi <= query[i].fi){
                int u = event[j + 1].se.fi;
                int v = event[j + 1].se.se;
                if (u + 1 == v){
                    unite(u , v , int(1e9));
                }
                else{
                    unite(u , v , a[id[u + 1]] - b[id[u + 1]]);
                    //cout << a[id[u + 1]] - b[id[u + 1]] << "\n";
                }
                j++;
            }
            res[query[i].se] = cur_ans;
        }
        //cout << Y[root(0)] << "\n";
    }
}

vector<long long> calculate_costs(vector<int> _w , vector<int> _a , vector<int> _b , vector<int> _e){
    w = _w; a = _a; b = _b; e = _e;
    n = sz(w) , q = sz(e);
    id.resize(n);
    for (int i = 0 ; i < n ; i++) id[i] = i;
    sort(all(id) , [](int x , int y){
         return w[x] < w[y];
    });
//    if (sub1::check()){
//        sub1::solve();
//        return res;
//    }
//    if (sub2::check()){
//        sub2::solve();
//        return res;
//    }
    sub3::solve();
    return res;
}

• Subtask 0: 0 / 0
• Subtask 1: 6 / 6
• Subtask 2: 13 / 13
• Subtask 3: 17 / 17
• Subtask 4: 11 / 11
• Subtask 5: 20 / 20
• Subtask 6: 15 / 15
• Subtask 7: 18 / 18