Cod sursa(job #1855404)

Utilizator SagunistuStrimbu Alexandru Sagunistu Data 23 ianuarie 2017 17:14:37
Problema Sortare prin comparare Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.96 kb
#include <fstream>
#include <climits>

using namespace std;

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

int a[500005],n;

void mrge(int a[],int p,int q,int r)
{
    int n1,n2,st[q-p+1],dr[r-q+1];
    n1 = q - p;
    n2 = r - q;
    for(int i=0;i<n1;i++)
        st[i]=a[p+i];
    for(int i=0;i<n2;i++)
        dr[i]=a[q+i];
    st[n1]=INT_MAX;
    dr[n2]=INT_MAX;
    int i = 0,j = 0;
    for(int k=p;k<r;k++)
    {
        if(st[i]<=dr[j])
        {
            a[k] = st[i];
            i++;
        }
        else
        {
            a[k] = dr[j];
            j++;
        }
    }
}

void mergeSort (int a[],int p,int r)
{
    if(p+1<r)
    {
        int q = (p+r)/2;
        mergeSort(a,p,q);
        mergeSort(a,q,r);
        mrge(a,p,q,r);
    }
}

int main()
{
    fin>>n;
    for(int i=0;i<n;i++)
        fin>>a[i];
    mergeSort(a,0,n);
    for(int i=0;i<n;i++)
        fout<<a[i]<<" ";
    return 0;
}