Cod sursa(job #1209931)

Utilizator daniel.amarieiDaniel Amariei daniel.amariei Data 18 iulie 2014 21:18:48
Problema Radix Sort Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.34 kb
#include <stdio.h>
#define MAX (1 << 20)
#define SIZE (1 << 30)
#define STEP 10
#define MASK_B1 255
#define MASK_B2 (MASK_B1 << 8)
#define MASK_B3 (MASK_B2 << 8)
#define MASK_B4 (MASK_B3 << 8)

int N, A, B, C;
int v[MAX], b1[MAX], b2[MAX], b3[MAX], b4[MAX], f[255];

void set_frequencies_to_zero() 
{
    for (int i = 0; i <= 255; ++i)
    {
        f[i] = 0;
    }
}

void sort_after_byte(int * v, int * b, int MASK)
{
    for (int i = 1; i <= N; ++i)
    {
        ++f[v[i] & MASK];      
    }
    
    for (int i = 1; i <= 255; ++i)
    {
        f[i] += f[i-1];
    }
    
    for (int i = N; i >= 1; --i)
    {
        b[f[v[i] & MASK]] = v[i];
        --f[v[i] & MASK];
    }
}

int main()
{
    freopen("radixsort.in", "r", stdin);
    freopen("radixsort.out", "w", stdout);
    
    scanf("%d %d %d %d", &N, &A, &B, &C);
    
    // Generam numerele
    v[1] = B;
    for (int i = 2; i <= N; ++i)
    {
        v[i] = (A * v[i-1] + B) % C;
    }

    // Sortare
    sort_after_byte(v, b1, MASK_B1);
    set_frequencies_to_zero();

    sort_after_byte(b1, b2, MASK_B2);
    set_frequencies_to_zero();

    sort_after_byte(b2, b3, MASK_B3);
    set_frequencies_to_zero();

    sort_after_byte(b3, b4, MASK_B4);
    set_frequencies_to_zero();
    
    // Afisare rezultat
    for (int i = 1; i <= N; i+=STEP)
    {
        printf("%d ", b4[i]);
    }

    return 0;
}