Submission #837518

#	Time	Username	Problem	Language	Result	Execution time	Memory
837518		oscar1f	Sorting (IOI15_sorting)	C++17	74 / 100	1081 ms	28040 KiB

sorting

#include<bits/stdc++.h>
#include "sorting.h"

using namespace std;

const int MAX_SWAP=600*1000+5;
int nbVal,nbSwap,posModif,nouvVal,deb,fin,mid;
int autreSwap[MAX_SWAP][2];
int val[MAX_SWAP];
int posDansObj[MAX_SWAP];
int obj[MAX_SWAP];
vector<pair<int,int>> nouv;
vector<pair<int,int>> rep;
set<int> listePb;
set<int>::iterator it;

void maj(int pos) {
    listePb.erase(pos);
    if (val[pos]!=obj[pos]) {
        listePb.insert(pos);
    }
}

int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
	nbVal=N;
	nbSwap=M;
	for (int i=0;i<nbVal;i++) {
		val[i]=S[i];
	}
	for (int i=0;i<nbSwap;i++) {
		autreSwap[i][0]=X[i];
		autreSwap[i][1]=Y[i];
	}
    fin=nbSwap;
	rep.resize(nbSwap);
	while (deb!=fin) {
		mid=(deb+fin)/2;
		nouv.clear();
        listePb.clear();
		for (int i=0;i<nbVal;i++) {
			obj[i]=i;
            posDansObj[i]=i;
		}
		for (int i=0;i<nbVal;i++) {
			val[i]=S[i];
		}
		for (int i=mid-1;i>=0;i--) {
            posDansObj[obj[autreSwap[i][0]]]=autreSwap[i][1];
            posDansObj[obj[autreSwap[i][1]]]=autreSwap[i][0];
			swap(obj[autreSwap[i][0]],obj[autreSwap[i][1]]);
		}
        for (int i=0;i<nbVal;i++) {
            maj(i);
        }
		for (int i=0;i<mid;i++) {
            posDansObj[obj[autreSwap[i][0]]]=autreSwap[i][1];
            posDansObj[obj[autreSwap[i][1]]]=autreSwap[i][0];
			swap(obj[autreSwap[i][0]],obj[autreSwap[i][1]]);
			swap(val[autreSwap[i][0]],val[autreSwap[i][1]]);
            maj(autreSwap[i][0]);
            maj(autreSwap[i][1]);
            if (listePb.empty()) {
                posModif=0;
            }
            else {
                it=listePb.begin();
                posModif=(*it);
            }
            nouvVal=posDansObj[val[posModif]];
			nouv.push_back({posModif,nouvVal});
			swap(val[posModif],val[nouvVal]);
            maj(posModif);
            maj(nouvVal);
		}
		if (!listePb.empty()) {
			deb=mid+1;
		}
		else {
			fin=mid;
			if (nouv.size()<rep.size()) {
				rep=nouv;
			}
		}
	}
	for (int i=0;i<deb;i++) {
		P[i]=rep[i].first;
		Q[i]=rep[i].second;
	}
	return deb;
}

• Subtask 1: 8 / 8
• Subtask 2: 12 / 12
• Subtask 3: 16 / 16
• Subtask 4: 18 / 18
• Subtask 5: 20 / 20
• Subtask 6: 0 / 26