Cod sursa(job #1238629)

Utilizator romircea2010FMI Trifan Mircea Mihai romircea2010 Data 7 octombrie 2014 13:24:49
Problema Sortare prin comparare Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.13 kb
#include <iostream>
#include <fstream>

using namespace std;

const int NMax = 500010;
int n;
int a[NMax], aux[NMax];

void Read()
{
    ifstream f ("algsort.in");
    f >> n;
    for (int i = 1; i <= n; ++ i)
        f >> a[i];
    f.close();
}

inline void MergeSort(const int st, const int dr)
{
    if (dr - st < 1)
        return ;
    if (dr - st == 1)
    {
        if (a[st] > a[dr])
            swap(a[st], a[dr]);
        return ;
    }
    int mij = (st+dr) >> 1;
    MergeSort(st, mij);
    MergeSort(mij + 1, dr);
    int i, j, poz = st - 1;
    i = st, j = mij + 1;
    while (i <= mij && j <= dr)
    {
        if (a[i] < a[j])
            aux[++poz] = a[i++];
        else
            aux[++poz] = a[j++];
    }
    while (i <= mij)
        aux[++poz] = a[i++];
    while (j <= dr)
        aux[++poz] = a[j++];
    for (int i = st; i <= dr; ++ i) a[i] = aux[i];
}

void Write()
{
    ofstream g ("algsort.out");
    for (int i = 1; i <= n; ++ i)
        g << a[i] << " ";
    g << "\n";
    g.close();
}

int main()
{
    Read();
    MergeSort(1, n);
    Write();
    return 0;
}