Submission #509824

#	Time	Username	Problem	Language	Result	Execution time	Memory
509824		sam571128	Palembang Bridges (APIO15_bridge)	C++17	22 / 100	531 ms	21188 KiB

bridge

#include <bits/stdc++.h>
#include <bits/extc++.h>

#define int long long
#define fastio ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

using namespace std;
using namespace __gnu_pbds;

const int N = 2e5+5;
pair<int,int> bit[N];
int now[N];

pair<int,int> operator + (pair<int,int> a, pair<int,int> b){
    return {a.first+b.first,a.second+b.second};
}

pair<int,int> operator - (pair<int,int> a, pair<int,int> b){
    return {a.first-b.first,a.second-b.second};
}

void update(int pos, pair<int,int> val){
    while(pos < N){
        bit[pos] = bit[pos] + val;
        pos += pos&-pos;
    }
}

pair<int,int> query(int pos){
    pair<int,int> res = {0,0};
    while(pos){
        res = res + bit[pos];
        pos -= pos&-pos;
    }
    return res;
}

typedef tree<pair<int,int>,null_type,less<pair<int,int>>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
int t;



signed main(){
    fastio
    int k, n;
    cin >> k >> n;

    vector<int> tmp;

    int ans = 1e18, anstmp = 0;

    vector<pair<int,int>> v;
    for(int i = 0;i < n;i++){
        char a,b;
        int x,y;
        cin >> a >> x >> b >> y;
        if(a == b) anstmp += abs(x-y);
        else{
            anstmp++;
            tmp.push_back(x);
            tmp.push_back(y);
            v.push_back({x,y});
        }
    }

    sort(tmp.begin(),tmp.end());
    sort(v.begin(),v.end(),[&](auto a, auto b){
        return a.first+a.second < b.first+b.second;
    });

    ordered_set s;
    for(int i = 0;i < v.size();i++){
        auto [x,y] = v[i];
        s.insert({x,t++});
        s.insert({y,t++});
        update(lower_bound(tmp.begin(),tmp.end(),x)-tmp.begin()+1,{1,x});
        update(lower_bound(tmp.begin(),tmp.end(),y)-tmp.begin()+1,{1,y});
        int med = (*s.find_by_order(s.size()/2)).first;
        pair<int,int> q1 =  query(N-1)-query(lower_bound(tmp.begin(),tmp.end(),med)-tmp.begin()+1), q2 = query(lower_bound(tmp.begin(),tmp.end(),med)-tmp.begin());


        now[i] = (q1.second-med*q1.first) + (med*q2.first-q2.second);
    }

    s.clear();
    fill(bit,bit+N,make_pair(0,0));

    for(int i = v.size()-1;i >= 1;i--){
        auto [x,y] = v[i];
        s.insert({x,t++});
        s.insert({y,t++});
        update(lower_bound(tmp.begin(),tmp.end(),x)-tmp.begin()+1,{1,x});
        update(lower_bound(tmp.begin(),tmp.end(),y)-tmp.begin()+1,{1,y});
        int med = (*s.find_by_order(s.size()/2)).first;
        pair<int,int> q1 =  query(N-1)-query(lower_bound(tmp.begin(),tmp.end(),med)-tmp.begin()+1), q2 = query(lower_bound(tmp.begin(),tmp.end(),med)-tmp.begin());

        ans = min(ans,now[i-1]+(q1.second-med*q1.first) + (med*q2.first-q2.second));
    }

    if(k==1){
        cout << now[v.size()-1] + anstmp << "\n";
    }else{
        cout << ans+anstmp << "\n";
    }
}

Compilation message (stderr)

bridge.cpp: In function 'int main()':
bridge.cpp:72:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   72 |     for(int i = 0;i < v.size();i++){
      |                   ~~^~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 14 / 14
• Subtask 3: 0 / 9
• Subtask 4: 0 / 32
• Subtask 5: 0 / 37