Cod sursa(job #460507)

Utilizator BitOneSAlexandru BitOne Data 2 iunie 2010 20:19:51
Problema Sortare prin comparare Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 2.33 kb
#include <cstdlib>
#include <fstream>
#include <iterator>
#define Nmax 500111

/*
 *
 */
using namespace std;
int v[Nmax];
inline void DownHeap( int k, int N )
{
    for( int son=2*k; son <= N; k=son, son*=2 )
    {
        if( son < N && v[son+1] > v[son] )
            ++son;
        if( v[k] >= v[son] )
            return;
        swap( v[k], v[son] );
    }
}
inline void HeapSort( int start, int end )
{
    for( int i=start+(end-start)/2; i >= start; --i )
        DownHeap( i, end );
    while( end >= start )
    {
        swap( v[start], v[end] );
        --end;
        DownHeap( start, end );
    }
}
inline int MedianOf3( int x, int y, int z )
{
    if( x >= y )
    {
        if( y >= z )
            return y;
        else if( z >= x )
                return x;
        return z;
    }
    else if( y >= z )
         {
             if( x >= z )
                return x;
             else return z;
         }
    return y;
}
inline void IntroSort( int left, int right, int depth_limit )
{
    if( left < right )
    {
        if( !depth_limit )
        {
            HeapSort( left, right );
            return;
        }
        int middle=left+(right-left)/2, lleft=left-1, rright=right+1, pValue=MedianOf3( v[left], v[middle], v[right] );
        while( true )
        {
            while( lleft <= right && pValue > v[++lleft] );
            while( rright > 0 && pValue < v[--rright] );
            if( lleft > rright )
                break;
            swap( v[lleft], v[rright] );
        }
        if( lleft < right )
            IntroSort( lleft, right, depth_limit-1 );
        if( rright > left )
            IntroSort( left, rright, depth_limit-1 );
    }
}
inline int Log2( int N )
{
    if( N <= 0 )
        return -1;
    int r=0;
    if( N >= 65536 )
        N>>=16, r+=16;
    if( N >= 256 )
        N>>=8, r+=8;
    if( N >= 16 )
        N>>=4, r+=4;
    if( N >= 4 )
        N>>=2, r+=2;
    if( N >= 2 )
        r+=1;
    return r;
}
int main( void )
{
    int N;
    ifstream in( "algsort.in" );
    in>>N;
    copy( istream_iterator<int>(in), istream_iterator<int>(), v+1 );
    IntroSort( 1, N, 4*Log2(N) );
    ofstream out( "algsort.out" );
    copy( v+1, v+N+1, ostream_iterator<int>(out, " " ) );
    out<<'\n';
    return EXIT_SUCCESS;
}