Cod sursa(job #984237)

Utilizator Impaler_009Mihai Nitu Impaler_009 Data 13 august 2013 21:05:50
Problema Sortare prin comparare Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.83 kb
#include <fstream>
#include <ctime>
#include <cstdlib>
#define maxn 500001

using namespace std;

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

int v[maxn],n;

void exchange (int &i, int &j)
{
    int temp=v[i];
    v[i]=v[j];
    v[j]=temp;
}

void quicksort (int p, int q)
{
    if (q<=p) return;

    int x=v[rand()%(q-p+1)+p],i=p-1,j=q+1,f=p,l=q;
    while (i<j)
    {
        do i++; while (v[i]<x);
        do j--; while (v[j]>x);
        if (i>=j) break;
        exchange (i,j);
        if (v[i]==x) {exchange (i,f); ++f;}
        if (v[j]==x) {exchange (j,l); --l;}
    }

    quicksort (p,j);
    quicksort (j+1,q);
}

int main()
{
    fin>>n;
    for (int i=1; i<=n; ++i) fin>>v[i];

    srand (time(NULL));
    quicksort (1,n);

    for (int i=1; i<=n; ++i) fout<<v[i]<<" ";
}