<|im_start|>system
You are a helpful AI assistant.<|im_end|>
<|im_start|>user
How can I iterate through each item in an array in a random order using c++?<|im_end|>
<|im_start|>assistant
I am assuming you only want to access each element once and don't want to modify the original array.

To do this you could start by making a new array of random indexes then using those indexes when accessing the array. This method has the advantage of not changing the original array. For example say you have an array of numbers **[6,8,13]** and you want to access this in random order. This array has a length 3 so you would create a new index array of this size with each possible index **[0,1,2]**.  Then you shuffle this array using the **std::random_shuffle** function to obtain an array like  **[1,2,0]**. Then when you iterate through your loop and access an element, you get the index from the index_array (which is in random order) to access your original array. This could look **my_array[index_array[i]]**.

Here is an example full program
```
#include <iostream> 
#include <algorithm>
#include <ctime>
#include <cstdlib>
                                                                                    
int main(){                                                 
        std::srand( unsigned (std::time(0)));//set seed 

        const int size_of_array = 3;//array length

        int my_array[size_of_array] = {6,8,13};//data

        int index_array[size_of_array];//index array
        int i;
        for(i = 0;i < size_of_array;i++) index_array[i] = i;//initialize indexes
        std::random_shuffle(index_array,index_array+size_of_array);//shuffle indexes

        for(i = 0;i < size_of_array;i++){//access in random order
                int random_index = index_array[i];
                std::cout << my_array[random_index] << std::endl;
        }

}
```<|im_end|>
<|im_start|>user
Why is the seed an unsigned number?<|im_end|>
<|im_start|>assistant
The `std::chrono::system_clock::now()` returns a std::chrono::time_point representing the current point in time.
To get the seed, you must first use the function `time_since_epoch()` provided by `std::chrono::duration`, which is a class returned by the aforementioned `now()` function. It represents the amount of time between a time point and the system clock's epoch. Then, you use the `count()` function, which returns the number of ticks for the duration.
The `count()` function by default returns an `unsigned int` number, since the number of ticks is always greater than or equal zero.
You can read more about the standard library header `chrono` [here](https://en.cppreference.com/w/cpp/header/chrono).<|im_end|>
<|im_start|>user
Are there any other ways to iterate though the array randomly?<|im_end|>
<|im_start|>assistant
Instead of shuffling the array you want to iterate through, you can create a shuffled "index array" stating the order of original array you are going to iterate through. Iterating through the index array in order is equivalent to iterating the input array randomly.

Let's say your input array is `input_array`. You can use the above code to generate `index_array`. Then you can iterate input array randomly by accessing `input_array[index_array[i]]`, where `i` is the loop variable.<|im_end|>