RadixSort

#include<fstream>
#define Nmax 1000001
using namespace std;
int a[Nmax];
int output[Nmax];

int getMax(int n) /// Calculeaza maximul din vectorul initial
{
	int maxX=a[0];
	for(int i=1;i<n;++i)
		if(a[i]>maxX)
			maxX=a[i];
	return maxX;
}

void countSort(int n,int exp) /// Counting Sort - se afla la baza RadixSort
{
	int i,count[32]={0};
	for(i=0;i<n;++i) /// Tinem minte numarul de aparitii in vectorul count
		count[(a[i]/exp)%32]++;
	for(i=1;i<32;++i) /// Modificam count[i] astfel incat count[i] sa contina pozitia cifrei din output[]
		count[i]+=count[i-1];
	for(i=n-1;i>=0;--i) /// Cream vectorul output
	{
		output[count[(a[i]/exp)%32]-1]=a[i];
		count[(a[i]/exp)%32]--;
	}
	for(i=0;i<n;++i) /// Copiem continutul vectorului output[] in a[]
		a[i]=output[i];
}

void radixsort(int n) /// Radix Sort
{
	int m=getMax(n); /// Calculam cel mai mare element pentru a afla numarul de cifre al acestuia
	for(int exp=1;m/exp>0;exp*=32) /// Folosim Counting Sort pentru fiecare cifra
		countSort(n,exp);
}

int main()
{
	ifstream f("radixsort.in");
	int n,i;
	f>>n;
	for(i=0;i<n;++i)
		f>>a[i];
	radixsort(n);
	f.close();
	ofstream g("radixsort.out");
	for(i=0;i<n;++i)
		(g<<a[i]).put(' ');
    g.close();
	return 0;
}