Submission #634147

# Submission time Handle Problem Language Result Execution time Memory
634147 2022-08-23T22:14:14 Z Mazza timeismoney (balkan11_timeismoney) C++14
80 / 100
1390 ms 804 KB
#pragma GCC optimize("Ofast")
//#pragma GCC optimization ("unroll-loops")
#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define int ll
#define vi vector<int>
#define vv vector<vi>
#define pb push_back
#define pi pair<int,int>
#define vvp vector<vector<pi>>

    int n,m;
struct edge{
    int a,b,t,c,idx;
};
vector<edge> edges;
vector<int> weight;
pi sol;
vector<pi> mstsol;
vector<pi> currmst;
struct dsu{

    vi par,size;
    int find(int i){
        return par[i] == i ? i : par[i] = find(par[i]);
    }
    void uni(int a, int b){
        a = find(a); b = find(b);
        if(a == b) return;
        if(size[a] < size[b]) swap(a,b);
        size[a] += size[b];
        par[b] = a;
    }
    dsu(int n){
        par.resize(n);
        iota(par.begin(), par.end(), 0);
        size.resize(n,1);
    }
};
pi solve(){
    sort(edges.begin(), edges.end(), [&](const edge &a, const edge &b){
        return weight[a.idx] < weight[b.idx];
    });

    dsu d(n);
    int tcost = 0, ccost = 0;
    currmst.clear();
    for(int i = 0; i < m; i++){
        edge &a = edges[i];
        if(d.find(a.a) != d.find(a.b)){
            tcost += a.t; ccost += a.c;
            d.uni(a.a, a.b);
            currmst.pb({a.a, a.b});
        }
    }

    return {tcost, ccost};
}
pi sub(pi a, pi b){
    return {a.first - b.first, a.second - b.second};
}
bool sopra(pi a, pi b){
    return (a.first * b.second - a.second * b.first >= 0);
}
signed main()
{
    cin.tie(0); cin.sync_with_stdio(0);cout.tie(0); cout.sync_with_stdio(0);
    cin>>n>>m;
    edges.resize(m); weight.resize(m);
    for(int i = 0; i < m; i++){
        edge a;
        cin>>a.a>>a.b>>a.t>>a.c;
        a.idx = i;
        edges[i] = a;
    }
    
    //soluzione ottimale per t
    for(int i = 0; i < m; i++){
        int idx = edges[i].idx;
        weight[idx] = edges[i].t;
    }
    pi a = solve();
    pi best = a;
    mstsol = currmst;

    //soluzione ottimale per c
    for(int i = 0; i < m; i++){
        int idx = edges[i].idx;
        weight[idx] = edges[i].c;
    }

    pi b = solve();
    //swap a e b se b best
    //area triangolo negativa quindi minimizzo per la migliore
    if((ll)best.first * best.second > (ll)b.first * b.second){
        best = b;
        mstsol = currmst;
        swap(a,b);
    }

    stack<pair<pi,pi>> s; s.push({a,b});
    while(!s.empty()){
        //change wwight
        a = s.top().first, b = s.top().second;
        s.pop();
        for(int i = 0; i < m; i++){
            int idx = edges[i].idx;
            weight[idx] = edges[i].c * (b.first - a.first) - edges[i].t * (b.second - a.second);
        }
        //run mst
        pi p = solve();
        //sopra retta a-b, punto peggiore
        if(sopra(sub(b,a), sub(p,a)) ){
            continue;
        }

        if((ll)best.first * best.second > (ll)p.first * p.second){
            best = p;
            mstsol = currmst;
        }

        s.push({a,p});
        s.push({p,b});
    }

    cout << best.first << " " << best.second << "\n";
    for(pi &a:mstsol){
        cout << a.first << " " << a.second << "\n";
    }

	return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 4 ms 804 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 0 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Incorrect 13 ms 340 KB Output isn't correct
15 Incorrect 8 ms 340 KB Output isn't correct
16 Correct 51 ms 340 KB Output is correct
17 Correct 54 ms 416 KB Output is correct
18 Correct 51 ms 340 KB Output is correct
19 Incorrect 1377 ms 724 KB Output isn't correct
20 Incorrect 1390 ms 724 KB Output isn't correct