Cod sursa(job #1605492)

Utilizator rapidu36Victor Manz rapidu36 Data 19 februarie 2016 07:17:05
Problema Sortare prin comparare Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.68 kb
#include <iostream>
#include <fstream>
#include <cstdlib>

using namespace std;

const int N = 500000;

ifstream in("algsort.in");
ofstream out("algsort.out");

int n, v[N];

inline void schimb(int &x, int &y)
{
    int aux = x;
    x = y;
    y = aux;
}

void citire(int v[], int &n)
{
    in >> n;
    for (int i = 0; i < n; i++)
        in >> v[i];
    in.close();
}

void amestecare(int v[], int n)
{
    int i, j;
    for (i = n - 1; i >= 0; i--)
    {
        j = rand() % (1 + i);
        schimb(v[i], v[j]);
    }
}

/*
int pivotare(int v[], int st, int dr)
{
    int i, j = st - 1;
    for (i = st; i < dr; i++)
        if (v[i] < v[dr])
        {
            ++j;
            if (j < i - 1)
                schimb(v[i], v[j]);
        }
    schimb(v[i], v[++j]);
    return j;
}

void sortare(int v[], int st, int dr)
{
    if (st >= dr)
        return;
    int p = pivotare(v, st, dr);
    sortare(v, st, p - 1);
    sortare(v, p + 1, dr);
}
*/

void pivotare(int v[], int st, int dr, int &p1, int &p2)
{
    int i;
    p1 = st;
    p2 = dr - 1;
    for (i = st; i <= p2; )
        if (v[i] < v[dr])
            schimb(v[i++], v[p1++]);
        else if (v[i] > v[dr])
            schimb(v[i], v[p2--]);
        else
            i++;
    schimb(v[dr], v[++p2]);
}

void sortare(int v[], int st, int dr)
{
    if (st >= dr)
        return;
    int p1, p2;
    pivotare(v, st, dr, p1, p2);
    sortare(v, st, p1 - 1);
    sortare(v, p2 + 1, dr);
}

void afisare(int v[], int n)
{
    out << v[0];
    for (int i = 1; i < n; i++)
        out << " " << v[i];
    out << "\n";
    out.close();
}

int main()
{
    citire(v, n);
    amestecare(v, n);
    sortare(v, 0, n - 1);
    afisare(v, n);
    return 0;
}