Submission #433842

#	Time	Username	Problem	Language	Result	Execution time	Memory
433842		Mounir	Bridges (APIO19_bridges)	C++14	0 / 100	403 ms	7212 KiB

bridges

#include <bits/stdc++.h>
#define chmax(x, v) x = max(x, v)
#define pii pair<int, int>
#define pb push_back
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
#define int long long
using namespace std;
     
const int N = 1e6;

struct Arete {
    int noeud, voisin, poids;

    bool operator < (const Arete &autre) const {
        if (poids != autre.poids)
            return poids < autre.poids;
        if (noeud != autre.noeud)
            return noeud < autre.noeud;
        return voisin < autre.voisin;
    }
};

struct Req {
    int iReq, poids, noeud;

    bool operator < (const Req &autre) const {
        if (poids != autre.poids)
            return poids < autre.poids;
        return iReq < autre.iReq;
    }
};

int ens[N], taille[N];

int getEns(int noeud){
    if (ens[noeud] != noeud)
        ens[noeud] = getEns(ens[noeud]);
    return ens[noeud];
}

int ans[N];

     
signed main(){
    int nNoeuds, nAretes; cin >> nNoeuds >> nAretes;
    vector<Arete> aretes;
    for (int iArete = 0; iArete < nAretes; ++iArete){
    	int noeud, voisin, poids; cin >> noeud >> voisin >> poids;
        aretes.pb({noeud, voisin, poids});
    }
    
    int nReqs; cin >> nReqs;
    vector<Req> reqs;
    for (int iReq = 0; iReq < nReqs; ++iReq){
        int type, noeud, poids; cin >> type >> noeud >> poids;
        reqs.pb({iReq, poids, noeud});
    }

    for (int noeud = 0; noeud <= nNoeuds; ++noeud)
        ens[noeud] = noeud, taille[noeud] = 1;

    sort(all(aretes));
    sort(all(reqs));
    int pt = 0, iArete = 0;
     while (pt < nReqs && reqs[pt].poids < aretes[0].poids){
        ans[reqs[pt].iReq] = taille[getEns(reqs[pt].noeud)];
        pt++;
      }


    for (Arete& arete : aretes){
        if (true){
            arete.noeud = getEns(arete.noeud);
            arete.voisin = getEns(arete.voisin);

            if (arete.noeud != arete.voisin){
                ens[arete.noeud] = arete.voisin;
                taille[arete.voisin] += taille[arete.noeud];
            }
        }
        
        int proc = 1e10;
        if (iArete + 1 != nAretes)
            proc = aretes[iArete+1].poids;

        while (pt < nReqs && reqs[pt].poids < proc){
            ans[reqs[pt].iReq] = taille[getEns(reqs[pt].noeud)];
            pt++;
        }


        ++iArete;
    }

    while (pt < nReqs)
        ans[reqs[pt++].iReq] = taille[getEns(reqs[pt].noeud)];

    for (int iReq = 0; iReq < nReqs; ++iReq){
        cout << ans[iReq] << endl;
    }
	return 0;
}

Compilation message (stderr)

bridges.cpp: In function 'int main()':
bridges.cpp:97:20: warning: operation on 'pt' may be undefined [-Wsequence-point]
   97 |         ans[reqs[pt++].iReq] = taille[getEns(reqs[pt].noeud)];
      |                  ~~^~

• Subtask 1: 0 / 13
• Subtask 2: 0 / 16
• Subtask 3: 0 / 17
• Subtask 4: 0 / 14
• Subtask 5: 0 / 13
• Subtask 6: 0 / 27