两个数组之间的多维数组组合

Question

I'm working on this project written in PHP which is essentially a webshop and I need to generate some XML showing which products are for sale.

Now, each product itself can have what's called attributes like, for example, height, color, shape, etc. And each attribute can have it's own properties like height. Height could be 120cm, 150cm, 180cm, etc..

There is no limit to how many attributes there can be or how many possible properties can be.

So, how would I find all combinations between theese 2 arrays?

Heres an example of a really stripped down product json: Let's just, for all intense of purposes, call this array $products once decoded.

{
    {
        "product_id":"1",
        "product_name":"Blommebladet tj\u00f8rn",
        "product_price":"400",
    },
    {
        "product_id":"2",
        "product_name":"Some other product",
        "product_price":"300",
    },
}

Looping through the products themselves is not hard. But, when looping through the products and getting the properties, it returns a new array which contains all attributes of the product and their properties. That's fairly easy too.

I need the system to generate a new list of products that has all the possible combinations of products without having to think about dealing with an extra array. I figured just making a new array of products and cramming the information on to those by copying the exsisting product and adding attributes/properties on to the existing info.

Attribute/Property stripped down version. This attribute belongs to the first product on my product list.

[{
    "attribute_name": "H\u00f8jde",
    "properties": {
        "359": {
            "property_name": "125 cm"
        },
        "356": {
            "property_name": "150 cm"
        },
        "357": {
            "property_name": "180 cm"
        },
        "358": {
            "property_name": "220 cm"
        }
    }
}] 

And here's an example of what I would like to happen. I'd like a new array, let's just call it $variants.

This should just copy the base products and add on the extra information to make them new "products". It's still the same base product so the id can't be changed.

The name should change to something like "Prod_name - [{Attr_name Prop_name},]" For example. like:

Blommebladet tj\ørn - H\øjde 125cm,
Blommebladet tj\ørn - H\øjde 150cm,
Blommebladet tj\ørn - H\øjde 160cm

Hope you get what I mean and help me! Thanks in advance.

Answer 1

You should look for combination algorithm that returns the value of x (attributes in your case) without repetitions. I can provide you with such, but written in C and you might find it useful and implement the logic in the language that your prefer.

#include <stdio.h>
#define MAXN 20
// Finds all combinations of n from k
const unsigned n = 5;
const unsigned k = 3;
unsigned mp[MAXN];
void print(unsigned length)
{
    unsigned i;
    for (i = 0; i < length; i++) printf("%u ", mp[i]);
    printf("\n");
}
void comb(unsigned i, unsigned after)
{
    unsigned j;
    if (i > k) return;
    for (j = after + 1; j <= n; j++) {
        mp[i - 1] = j;
        if (i == k) print(i);
        comb(i + 1, j);
    }
}

int main() {
    printf("C(%u,%u): \n", n, k);
    comb(1, 0);
    return 0;
}


    /* Results:
    1 2 3
    1 2 4
    1 2 5
    1 3 4
    1 3 5
    1 4 5
    2 3 4
    2 3 5
    2 4 5
    3 4 5  
*/