#ifndef __RA_ARRAY__
#define __RA_ARRAY__
#include <intrin.h>
#define ULONG unsigned long
template <typename T>
class random_access_array{
const ULONG elements;
const ULONG R;
ULONG a;
ULONG c;
T* buffer;
const ULONG nextPowerOf2(ULONG n)const{
if ((n & (n - 1)) == 0)
return n;
n |= (n >> 1);
n |= (n >> 2);
n |= (n >> 4);
n |= (n >> 8);
n |= (n >> 16);
return n + 1;
}
ULONG LCG(ULONG X, ULONG a, ULONG c, ULONG R){
return (a*X + c) % R;
}
ULONG randmax(ULONG max){
return LCG((ULONG) __rdtsc(), 0x43FD43FDUL, 0xC39EC3UL, max);
}
size_t getRealIdx(int index){
ULONG X = 0;
while (index-- >= 0)
while ((X = LCG(X, a, c, R)) >= elements){}
return X;
}
public:
random_access_array(T* buffer, size_t elements) : elements(elements), buffer(buffer), R(nextPowerOf2(elements)){
a = 2 * randmax(R / 2) + 1;
c = 4 * randmax(R / 4) + 1;
}
random_access_array(T* buffer, size_t elements, ULONG a, ULONG c) : elements(elements), buffer(buffer), R(nextPowerOf2(elements)), a(a), c(c){}
T& operator [](size_t i){
return buffer[getRealIdx(i)];
}
T operator [](const size_t i) const{
return buffer[getRealIdx(i)];
}
};
#endif//__RA_ARRAY__Ejemplo de uso:
#define SIZE 573
random_access_array<int> ra(new int[SIZE], SIZE);
for (int i = 0; i < SIZE; i++)
ra[i] = i;
for (int i = 0; i < SIZE; i++)
cout << ra[i] << endl;Utilidad real:
#define SIZE sizeof(s) - 1
char s[] = "!eru!akklccr !rza";
random_access_array<char> ra(s, SIZE, 5, 25);
for (int i = 0; i < SIZE; i++)
cout << ra[i];Saludos
No pongo código de ejemplo para dejar algo de trabajo al lector 
:xD
