Cod sursa(job #1021924)

Utilizator dan.ghitaDan Ghita dan.ghita Data 4 noiembrie 2013 14:47:10
Problema Sortare prin comparare Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.17 kb
#include<iostream>
#include<fstream>
#include<ctime>
#include<cstdlib>
#include<algorithm>
using namespace std;
ifstream f("algsort.in");
ofstream g("algsort.out");
int v[500001], n;
int pivot(int left, int right)
{
    int p1,p2,p3,p,mini,maxi;
    p1=v[left + rand() % (right-left+1)];
    p2=v[left + rand() % (right-left+1)];
    p3=v[left + rand() % (right-left+1)];
    if(p1<=p2&&p1<=p3)
        mini=p1;
    if(p2<=p1&&p2<=p3)
        mini=p2;
    if(p3<=p1&&p3<=p2)
        mini=p3;
    if(p1>=p2&&p1>=p3)
        maxi=p1;
    if(p2>=p1&&p2>=p3)
        maxi=p2;
    if(p3>=p1&&p3>=p2)
        maxi=p3;
    p=p1+p2+p3-maxi-mini;
    return p;

}
void qsort(int a, int b)
{
    int i=a, j=b;
    srand(time(0));
    int p=pivot(a, b);
    while(i<=j)
    {
        while(v[i]<p)
            ++i;
        while(v[j]>p)
            --j;
        if(i<=j)
            swap(v[i], v[j]), ++i, --j;
    }
    if(a<j)
        qsort(a,j);
    if(i<b)
        qsort(i,b);

}
int main()
{
    int u;
    f>>n;
    for(int i=0;i<n;i++)
        f>>v[i];
    qsort(0,n-1);
    for(int i=0;i<n;i++)
        g<<v[i]<<" ";

    return 0;
}