Cod sursa(job #2278270)

Utilizator pasoi_stefanPasoi Stefan pasoi_stefan Data 7 noiembrie 2018 15:51:02
Problema Sortare prin comparare Scor 60
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.01 kb
#include<fstream>
#include<cstdlib>
#include<time.h>
using namespace std;
ifstream cin("algsort.in");
ofstream cout("algsort.out");
int n,v[500005];
int chose_pivot(int s,int d){
    int r1,r2,r3;
    r1=rand()%(d-s+1)+s;
    r2=rand()%(d-s+1)+s;
    r3=rand()%(d-s+1)+s;
    if(v[r1]<=v[r2] && v[r1]<=v[r3])
            return (v[r2]<=v[r3]?v[r2]:v[r3]);
    if(v[r2]<=v[r1] && v[r2]<=v[r3])
            return (v[r1]<=v[r3]?v[r1]:v[r3]);
    if(v[r3]<=v[r1] && v[r3]<=v[r2])
            return (v[r1]<=v[r2]?r1:v[r2]);
}
void quicksort(int s,int d){
    if(d-s+1<=1) return;
    int pivot=chose_pivot(s,d),i=s,j=d;
    while(i<=j){
        while(v[i]<pivot) ++i;
        while(v[j]>pivot) --j;
        if(i<=j){
            swap(v[i],v[j]);
            ++i; --j;
        }
    }
    quicksort(s,j);
    quicksort(i,d);
}
int main(){
    srand(time(NULL));
    cin>>n;
    for(int i=1;i<=n;i++)
        cin>>v[i];
    quicksort(1,n);
    for(int i=1;i<=n;i++)
        cout<<v[i]<<' ';
}