Cod sursa(job #1537867)

Utilizator theo.stoicanTheodor Stoican theo.stoican Data 28 noiembrie 2015 11:22:11
Problema Radix Sort Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 2.35 kb
// C++ implementation of Radix Sort
#include <iostream>
#include <fstream>
#include <vector>
#include <limits.h>
using namespace std;

int n, a, b, c;

// A utility function to get maximum value in arr[]
int getMax(int arr[], int n)
{
    int mx = arr[0];
    for (int i = 1; i < n; i++)
        if (arr[i] > mx)
            mx = arr[i];
    return mx;
}
 
// A function to do counting sort of arr[] according to
// the digit represented by exp.
void countSort(int arr[], int n, int exp)
{
    //int output[n]; // output array
    int *output = new int[n];
    int i, count[10] = {0};
 
    // Store count of occurrences in count[]
    for (i = 0; i < n; i++)
        count[ (arr[i]/exp)%10 ]++;
 
    // Change count[i] so that count[i] now contains actual
    //  position of this digit in output[]
    for (i = 1; i < 10; i++)
        count[i] += count[i - 1];
 
    // Build the output array
    for (i = n - 1; i >= 0; i--)
    {
        output[count[ (arr[i]/exp)%10 ] - 1] = arr[i];
        count[ (arr[i]/exp)%10 ]--;
    }
 
    // Copy the output array to arr[], so that arr[] now
    // contains sorted numbers according to current digit
    for (i = 0; i < n; i++)
        arr[i] = output[i];
}
 
// The main function to that sorts arr[] of size n using 
// Radix Sort
void radixsort(int arr[], int n)
{
    // Find the maximum number to know number of digits
    int m = getMax(arr, n);
 
    // Do counting sort for every digit. Note that instead
    // of passing digit number, exp is passed. exp is 10^i
    // where i is current digit number
    for (int exp = 1; m/exp > 0; exp *= 10)
        countSort(arr, n, exp);
}
 
// A utility function to print an array
void print(int arr[], int n)
{
    for (int i = 0; i < n; i++)
        cout << arr[i] << " ";
}
void generateVector(int n, int arr[])
{
    arr[0]=b;
    for (int i = 1;i<=n-1;++i){
        arr[i] = (a*arr[i-1]+b)%c;
    }
}
// Driver program to test above functions
int main()
{
    ofstream radixOut;
    ifstream radixIn;
    radixIn.open("radixsort.in");
    radixOut.open("radixsort.out");
    radixIn>>n;
    radixIn>>a;
    radixIn>>b>>c;
    //int arr[n];// = {170, 45, 75, 90, 802, 24, 2, 66};
    //int n = sizeof(arr)/sizeof(arr[0]);
    int *arr = new int[n];
    generateVector(n, arr);
    radixsort(arr, n);
    //print(arr, n);
    for (int i = 0; i<n;i+=10)
        radixOut << arr[i] << " ";
    return 0;
}