Cod sursa(job #2775908)

Utilizator caesar2001Stoica Alexandru caesar2001 Data 17 septembrie 2021 22:59:07
Problema Heapuri Scor 20
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 2.5 kb
#include <bits/stdc++.h>
#define ll long long
#define lsb(x) x & -x

using namespace std;

class Heap {
private:
    vector<int> heap;
    vector<int> heapToPos; //pos in heap -> pos in reality
    vector<int> posToHeap; //pos in reality -> pos in heap
    vector<int> elements;
    int size = 0;
public:
    Heap() {
        heap.resize(1, 0);
        heapToPos.resize(1, 0);
        posToHeap.resize(1, 0);
        elements.resize(1, 0);
    }

    void swapNodes(int a, int b) {
        swap(heap[a], heap[b]);
        swap(heapToPos[a], heapToPos[b]);
        swap(posToHeap[heapToPos[a]], posToHeap[heapToPos[b]]);
    }

    void goUP(int node) {
        if(node == 1)
            return;
        if(heap[node] < heap[node / 2]) {
            swapNodes(node, node / 2);
            goUP(node / 2);
        }
    }

    void add(int x) {
        size ++;
        heap.push_back(x);
        heapToPos.push_back(elements.size());
        posToHeap.push_back(size);
        elements.push_back(x);
        goUP(size);
    }

    void goDOWN(int node) {
        int dest = -1;
        if(node * 2 <= size && heap[node] > heap[node * 2])
            dest = node * 2;
        if(node * 2 + 1 <= size && heap[node] > heap[node * 2 + 1])
            dest = node * 2 + 1;
        if(dest != -1) {
            swapNodes(node, dest);
            goDOWN(dest);
        }
    }

    void remove(int pos) {
        int tmp = posToHeap[pos]; ///aici!!!
        swapNodes(size, posToHeap[pos]);
        //print();
        heap.pop_back();
        heapToPos.pop_back();
        size --;
        if(tmp <= size) {
            goUP(tmp);
            goDOWN(tmp);
        }
        posToHeap[pos] = -1;
    }

    int getMin() {
        return heap[1];
    }

    void print() {
        for(auto it : heap)
            cout << it << " ";
        cout << endl;
        for(auto it : heapToPos)
            cout << it << " ";
        cout << endl;
        for(auto it : posToHeap)
            cout << it << " ";
        cout << endl;
        cout << endl;
    }

};

int main() {
    ifstream cin("heapuri.in");
    ofstream cout("heapuri.out");

    int ntests;
    cin >> ntests;

    Heap myHeap;
    while(ntests --) {
        int type;
        cin >> type;
        if(type == 1) {
            int x;
            cin >> x;
            myHeap.add(x);
        } else if(type == 2) {
            int x;
            cin >> x;
            myHeap.remove(x);
        } else {
            cout << myHeap.getMin() << "\n";
        }
        //myHeap.print();
    }

    return 0;
}