Arduino language shuffle order of an array - arrays

Question

I'm working with arduino , but I can't seem to shuffle an array.
the proplem is that with arduino I can't use an arraylist so hat makes it very hard for me to shuffle the array.
What I actually want is a list of numbers from 0 to 52 shuffled. so every time I run the program it is shuffled in a different order with the numbers from 0 to 52
Here is my code:
const int MAXNUMMER = 52;
int numbers[52];
int temp = numbers[first];
//int numbers[first] = numbers[second];
//int numbers[second] = temp;
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
randomizeList();
}
void loop() {
// put your main code here, to run repeatedly:
}
void randomizeList()
{
randomSeed(analogRead(A0));
int r = random(53);
for(int i =0; i < MAXNUMMER; i++)
{
if(numbers[i] != r)
{
numbers[i] = r;
Serial.println(numbers[i]);
}
}
}

Answer 1

I tested this and it should work. I just used the Serial.print in the function because I wanted to see all the at the end ;)
const int NUMOFNUMBERS = 52;
int numbers[NUMOFNUMBERS];
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
randomizeList();
}
void loop() {
// put your main code here, to run repeatedly:
}
void randomizeList()
{
unsigned char chosen[NUMOFNUMBERS];
unsigned char index, i2;
for (index = 0; index < NUMOFNUMBERS; index++)
chosen[index] = 0;
randomSeed(analogRead(A0));
for (index = 0; index < NUMOFNUMBERS; index++)
{
int r = random(NUMOFNUMBERS-index);
for (i2 = 0; i2 <= r; i2++)
{
r += chosen[i2];
}
chosen[r] = 1;
numbers[index] = r;
Serial.print(numbers[index]);
Serial.print(" ");
}
Serial.println("");
}
I changed the name of the variable from MAXNUMMER to NUMOFNUMBERS because it is the number of numbers to be generated (i.e. the maximum number will be NUMOFNUMBERS - 1
This is an example running this program for 6 times setting NUMOFNUMBERS to 5:
4 1 3 2 0
2 3 4 0 1
1 0 2 4 3
0 4 1 3 2
3 0 4 2 1
4 3 2 1 0
EDIT: If you want to randomize the list more than once, I suggest you to move the randomSeed function from the function to the setup function. This way you will be able to call randomizeList every time you want.
One more thing: if you prefer to have a list with values [1,52] instead of [0,51] you can just edit the line numbers[index] = r; into numbers[index] = r + 1;