Cod sursa(job #1004881)

Utilizator ioalexno1Alexandru Bunget ioalexno1 Data 3 octombrie 2013 19:25:55
Problema Sortare prin comparare Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.93 kb
#include <cstdio>
#include <cstring>
using namespace std;
int a[500005],n;
void mergesort(int,int,int);
void interclasare(int,int,int);
void read()
{
freopen("grader_test14.in","r",stdin); scanf("%d\n",&n); for(int i=1;i<=n;++i)scanf("%d ",&a[i]); fclose(stdin);
}
void mergesort(int st,int dr)
{
if(st<dr)
    {
    int mid=(st+dr)/2;
    mergesort(st,mid);
    mergesort(mid+1,dr);
    interclasare(st,mid,dr);
    }
}
void interclasare(int st,int mid,int dr)
{
int b[500005],i=st,j=mid+1,k=0,h;
memset(b,0,sizeof(b));
while(i<=mid&&j<=dr)
    {
    if(a[i]<a[j]){ b[++k]=a[i]; ++i; } else { b[++k]=a[j]; ++j; }
    }
if(i>mid)for(h=j;h<=dr;++h)b[++k]=a[h]; else for(h=i;h<=mid;++h)b[++k]=a[h];
j=1; for(i=st;i<=dr;++i){ a[i]=b[j]; ++j; }
}
void write()
{
freopen("algsort.out","w",stdout); for(int i=1;i<=n;++i)printf("%d ",a[i]); fclose(stdout);
}
int main()
{
read();
mergesort(1,n);
write();
return 0;
}