a little function

[catus]

hi all.
i wrote this

int crea_vett ( int vett[], int size )



{
int indice;
int poss[9] = {1, 2, 3, 4, 5, 6, 7, 8, 9};

srand( time( NULL ));

for ( int i = 0 ; i < size ; i++ ) {
indice = rand()%9 + 1;
while ( poss[indice] == 0 )
indice = rand()%9 + 1;
vett[i] = poss[indice];
poss[indice] = 0;
}
return 0;
}

a little function for the creation of a 4 different elements array. the elements have value from 1 to 9 and are chosen by the function rand().

that's the problem: running it, sometime i obtain value like 1330021354561 for an element!!
where's my error?? =(

[Bourgond Aries]

Indice can be 9, but the valid element ranges are 0-8 (9 different elements). Use indicde = rand()%9; instead of +1.

[CroCo]

Would you please save our time by putting the entire code. And why your function like that. it is messed up.

#include <iostream>
#include <cstdlib>     
#include <ctime>     

int const SIZE = 4;

void crea_vett(int vett[], const int& size )
{
    srand( (unsigned int)time( NULL ));	
	for ( int i = 0 ; i < size ; i++ )
	{
		vett[i] = rand()%9 + 1;
		std::cout << vett[i] << std::endl;
	}
}

int main()
{
	int vett[SIZE] = {0};
	crea_vett(vett, SIZE);
	std::cin.get();
	return 0;
}

[vlad from moscow]

This code is wrong

indice = rand()%9 + 1;
while ( poss[indice] == 0 )
indice = rand()%9 + 1;
vett[i] = poss[indice];

If an array has N elements its indexes are in the range [0, N-1]

You are genereating indexes in the range [1, 9] for an array that has 9 elements.